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Green_GoodERP18_FSJ_Standard/python/Doc/html/whatsnew/3.11.html

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  97.     <ul>

  98. <li><a class="reference internal" href="#">What’s New In Python 3.11</a><ul>

  99. <li><a class="reference internal" href="#summary-release-highlights">Summary – Release highlights</a></li>

  100. <li><a class="reference internal" href="#new-features">New Features</a><ul>

  101. <li><a class="reference internal" href="#pep-657-fine-grained-error-locations-in-tracebacks">PEP 657: Fine-grained error locations in tracebacks</a></li>

  102. <li><a class="reference internal" href="#pep-654-exception-groups-and-except">PEP 654: Exception Groups and <code class="docutils literal notranslate"><span class="pre">except*</span></code></a></li>

  103. <li><a class="reference internal" href="#pep-678-exceptions-can-be-enriched-with-notes">PEP 678: Exceptions can be enriched with notes</a></li>

  104. <li><a class="reference internal" href="#windows-py-exe-launcher-improvements">Windows <code class="docutils literal notranslate"><span class="pre">py.exe</span></code> launcher improvements</a></li>

  105. </ul>

  106. </li>

  107. <li><a class="reference internal" href="#new-features-related-to-type-hints">New Features Related to Type Hints</a><ul>

  108. <li><a class="reference internal" href="#pep-646-variadic-generics">PEP 646: Variadic generics</a></li>

  109. <li><a class="reference internal" href="#pep-655-marking-individual-typeddict-items-as-required-or-not-required">PEP 655: Marking individual <code class="docutils literal notranslate"><span class="pre">TypedDict</span></code> items as required or not-required</a></li>

  110. <li><a class="reference internal" href="#pep-673-self-type">PEP 673: <code class="docutils literal notranslate"><span class="pre">Self</span></code> type</a></li>

  111. <li><a class="reference internal" href="#pep-675-arbitrary-literal-string-type">PEP 675: Arbitrary literal string type</a></li>

  112. <li><a class="reference internal" href="#pep-681-data-class-transforms">PEP 681: Data class transforms</a></li>

  113. <li><a class="reference internal" href="#pep-563-may-not-be-the-future">PEP 563 may not be the future</a></li>

  114. </ul>

  115. </li>

  116. <li><a class="reference internal" href="#other-language-changes">Other Language Changes</a></li>

  117. <li><a class="reference internal" href="#other-cpython-implementation-changes">Other CPython Implementation Changes</a></li>

  118. <li><a class="reference internal" href="#new-modules">New Modules</a></li>

  119. <li><a class="reference internal" href="#improved-modules">Improved Modules</a><ul>

  120. <li><a class="reference internal" href="#asyncio">asyncio</a></li>

  121. <li><a class="reference internal" href="#contextlib">contextlib</a></li>

  122. <li><a class="reference internal" href="#dataclasses">dataclasses</a></li>

  123. <li><a class="reference internal" href="#datetime">datetime</a></li>

  124. <li><a class="reference internal" href="#enum">enum</a></li>

  125. <li><a class="reference internal" href="#fcntl">fcntl</a></li>

  126. <li><a class="reference internal" href="#fractions">fractions</a></li>

  127. <li><a class="reference internal" href="#functools">functools</a></li>

  128. <li><a class="reference internal" href="#hashlib">hashlib</a></li>

  129. <li><a class="reference internal" href="#whatsnew311-idle">IDLE and idlelib</a></li>

  130. <li><a class="reference internal" href="#inspect">inspect</a></li>

  131. <li><a class="reference internal" href="#locale">locale</a></li>

  132. <li><a class="reference internal" href="#logging">logging</a></li>

  133. <li><a class="reference internal" href="#math">math</a></li>

  134. <li><a class="reference internal" href="#operator">operator</a></li>

  135. <li><a class="reference internal" href="#os">os</a></li>

  136. <li><a class="reference internal" href="#pathlib">pathlib</a></li>

  137. <li><a class="reference internal" href="#re">re</a></li>

  138. <li><a class="reference internal" href="#shutil">shutil</a></li>

  139. <li><a class="reference internal" href="#socket">socket</a></li>

  140. <li><a class="reference internal" href="#sqlite3">sqlite3</a></li>

  141. <li><a class="reference internal" href="#string">string</a></li>

  142. <li><a class="reference internal" href="#sys">sys</a></li>

  143. <li><a class="reference internal" href="#sysconfig">sysconfig</a></li>

  144. <li><a class="reference internal" href="#tempfile">tempfile</a></li>

  145. <li><a class="reference internal" href="#threading">threading</a></li>

  146. <li><a class="reference internal" href="#time">time</a></li>

  147. <li><a class="reference internal" href="#tkinter">tkinter</a></li>

  148. <li><a class="reference internal" href="#traceback">traceback</a></li>

  149. <li><a class="reference internal" href="#typing">typing</a></li>

  150. <li><a class="reference internal" href="#unicodedata">unicodedata</a></li>

  151. <li><a class="reference internal" href="#unittest">unittest</a></li>

  152. <li><a class="reference internal" href="#venv">venv</a></li>

  153. <li><a class="reference internal" href="#warnings">warnings</a></li>

  154. <li><a class="reference internal" href="#zipfile">zipfile</a></li>

  155. </ul>

  156. </li>

  157. <li><a class="reference internal" href="#optimizations">Optimizations</a></li>

  158. <li><a class="reference internal" href="#faster-cpython">Faster CPython</a><ul>

  159. <li><a class="reference internal" href="#faster-startup">Faster Startup</a><ul>

  160. <li><a class="reference internal" href="#frozen-imports-static-code-objects">Frozen imports / Static code objects</a></li>

  161. </ul>

  162. </li>

  163. <li><a class="reference internal" href="#faster-runtime">Faster Runtime</a><ul>

  164. <li><a class="reference internal" href="#cheaper-lazy-python-frames">Cheaper, lazy Python frames</a></li>

  165. <li><a class="reference internal" href="#inlined-python-function-calls">Inlined Python function calls</a></li>

  166. <li><a class="reference internal" href="#pep-659-specializing-adaptive-interpreter">PEP 659: Specializing Adaptive Interpreter</a></li>

  167. </ul>

  168. </li>

  169. <li><a class="reference internal" href="#misc">Misc</a></li>

  170. <li><a class="reference internal" href="#faq">FAQ</a><ul>

  171. <li><a class="reference internal" href="#how-should-i-write-my-code-to-utilize-these-speedups">How should I write my code to utilize these speedups?</a></li>

  172. <li><a class="reference internal" href="#will-cpython-3-11-use-more-memory">Will CPython 3.11 use more memory?</a></li>

  173. <li><a class="reference internal" href="#i-don-t-see-any-speedups-in-my-workload-why">I don’t see any speedups in my workload. Why?</a></li>

  174. <li><a class="reference internal" href="#is-there-a-jit-compiler">Is there a JIT compiler?</a></li>

  175. </ul>

  176. </li>

  177. <li><a class="reference internal" href="#about">About</a></li>

  178. </ul>

  179. </li>

  180. <li><a class="reference internal" href="#cpython-bytecode-changes">CPython bytecode changes</a><ul>

  181. <li><a class="reference internal" href="#new-opcodes">New opcodes</a></li>

  182. <li><a class="reference internal" href="#replaced-opcodes">Replaced opcodes</a></li>

  183. <li><a class="reference internal" href="#changed-removed-opcodes">Changed/removed opcodes</a></li>

  184. </ul>

  185. </li>

  186. <li><a class="reference internal" href="#deprecated">Deprecated</a><ul>

  187. <li><a class="reference internal" href="#language-builtins">Language/Builtins</a></li>

  188. <li><a class="reference internal" href="#modules">Modules</a></li>

  189. <li><a class="reference internal" href="#standard-library">Standard Library</a></li>

  190. </ul>

  191. </li>

  192. <li><a class="reference internal" href="#pending-removal-in-python-3-12">Pending Removal in Python 3.12</a></li>

  193. <li><a class="reference internal" href="#removed">Removed</a></li>

  194. <li><a class="reference internal" href="#porting-to-python-3-11">Porting to Python 3.11</a></li>

  195. <li><a class="reference internal" href="#build-changes">Build Changes</a></li>

  196. <li><a class="reference internal" href="#c-api-changes">C API Changes</a><ul>

  197. <li><a class="reference internal" href="#whatsnew311-c-api-new-features">New Features</a></li>

  198. <li><a class="reference internal" href="#whatsnew311-c-api-porting">Porting to Python 3.11</a></li>

  199. <li><a class="reference internal" href="#whatsnew311-c-api-deprecated">Deprecated</a></li>

  200. <li><a class="reference internal" href="#whatsnew311-c-api-pending-removal">Pending Removal in Python 3.12</a></li>

  201. <li><a class="reference internal" href="#whatsnew311-c-api-removed">Removed</a></li>

  202. </ul>

  203. </li>

  204. <li><a class="reference internal" href="#notable-changes-in-3-11-4">Notable changes in 3.11.4</a><ul>

  205. <li><a class="reference internal" href="#tarfile">tarfile</a></li>

  206. </ul>

  207. </li>

  208. <li><a class="reference internal" href="#notable-changes-in-3-11-5">Notable changes in 3.11.5</a><ul>

  209. <li><a class="reference internal" href="#openssl">OpenSSL</a></li>

  210. </ul>

  211. </li>

  212. </ul>

  213. </li>

  214. </ul>

  215. 

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  218.     <h4>Previous topic</h4>

  219.     <p class="topless"><a href="3.12.html"

  220.                           title="previous chapter">What’s New In Python 3.12</a></p>

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  303.   <section id="what-s-new-in-python-3-11">

  304. <h1>What’s New In Python 3.11<a class="headerlink" href="#what-s-new-in-python-3-11" title="Link to this heading">¶</a></h1>

  305. <dl class="field-list simple">

  306. <dt class="field-odd">Editor<span class="colon">:</span></dt>

  307. <dd class="field-odd"><p>Pablo Galindo Salgado</p>

  308. </dd>

  309. </dl>

  310. <p>This article explains the new features in Python 3.11, compared to 3.10.

  311. Python 3.11 was released on October 24, 2022.

  312. For full details, see the <a class="reference internal" href="changelog.html#changelog"><span class="std std-ref">changelog</span></a>.</p>

  313. <section id="summary-release-highlights">

  314. <span id="whatsnew311-summary"></span><h2>Summary – Release highlights<a class="headerlink" href="#summary-release-highlights" title="Link to this heading">¶</a></h2>

  315. <ul class="simple">

  316. <li><p>Python 3.11 is between 10-60% faster than Python 3.10.

  317. On average, we measured a 1.25x speedup on the standard benchmark suite.

  318. See <a class="reference internal" href="#whatsnew311-faster-cpython"><span class="std std-ref">Faster CPython</span></a> for details.</p></li>

  319. </ul>

  320. <p>New syntax features:</p>

  321. <ul class="simple">

  322. <li><p><a class="reference internal" href="#whatsnew311-pep654"><span class="std std-ref">PEP 654: Exception Groups and except*</span></a></p></li>

  323. </ul>

  324. <p>New built-in features:</p>

  325. <ul class="simple">

  326. <li><p><a class="reference internal" href="#whatsnew311-pep678"><span class="std std-ref">PEP 678: Exceptions can be enriched with notes</span></a></p></li>

  327. </ul>

  328. <p>New standard library modules:</p>

  329. <ul class="simple">

  330. <li><p><span class="target" id="index-0"></span><a class="pep reference external" href="https://peps.python.org/pep-0680/"><strong>PEP 680</strong></a>: <a class="reference internal" href="../library/tomllib.html#module-tomllib" title="tomllib: Parse TOML files."><code class="xref py py-mod docutils literal notranslate"><span class="pre">tomllib</span></code></a> —

  331. Support for parsing <a class="reference external" href="https://toml.io/">TOML</a> in the Standard Library</p></li>

  332. </ul>

  333. <p>Interpreter improvements:</p>

  334. <ul class="simple">

  335. <li><p><a class="reference internal" href="#whatsnew311-pep657"><span class="std std-ref">PEP 657: Fine-grained error locations in tracebacks</span></a></p></li>

  336. <li><p>New <a class="reference internal" href="../using/cmdline.html#cmdoption-P"><code class="xref std std-option docutils literal notranslate"><span class="pre">-P</span></code></a> command line option and <span class="target" id="index-1"></span><a class="reference internal" href="../using/cmdline.html#envvar-PYTHONSAFEPATH"><code class="xref std std-envvar docutils literal notranslate"><span class="pre">PYTHONSAFEPATH</span></code></a> environment

  337. variable to <a class="reference internal" href="#whatsnew311-pythonsafepath"><span class="std std-ref">disable automatically prepending potentially unsafe paths</span></a> to <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a></p></li>

  338. </ul>

  339. <p>New typing features:</p>

  340. <ul class="simple">

  341. <li><p><a class="reference internal" href="#whatsnew311-pep646"><span class="std std-ref">PEP 646: Variadic generics</span></a></p></li>

  342. <li><p><a class="reference internal" href="#whatsnew311-pep655"><span class="std std-ref">PEP 655: Marking individual TypedDict items as required or not-required</span></a></p></li>

  343. <li><p><a class="reference internal" href="#whatsnew311-pep673"><span class="std std-ref">PEP 673: Self type</span></a></p></li>

  344. <li><p><a class="reference internal" href="#whatsnew311-pep675"><span class="std std-ref">PEP 675: Arbitrary literal string type</span></a></p></li>

  345. <li><p><a class="reference internal" href="#whatsnew311-pep681"><span class="std std-ref">PEP 681: Data class transforms</span></a></p></li>

  346. </ul>

  347. <p>Important deprecations, removals and restrictions:</p>

  348. <ul class="simple">

  349. <li><p><span class="target" id="index-2"></span><a class="pep reference external" href="https://peps.python.org/pep-0594/"><strong>PEP 594</strong></a>:

  350. <a class="reference internal" href="#whatsnew311-pep594"><span class="std std-ref">Many legacy standard library modules have been deprecated</span></a> and will be removed in Python 3.13</p></li>

  351. <li><p><span class="target" id="index-3"></span><a class="pep reference external" href="https://peps.python.org/pep-0624/"><strong>PEP 624</strong></a>:

  352. <a class="reference internal" href="#whatsnew311-pep624"><span class="std std-ref">Py_UNICODE encoder APIs have been removed</span></a></p></li>

  353. <li><p><span class="target" id="index-4"></span><a class="pep reference external" href="https://peps.python.org/pep-0670/"><strong>PEP 670</strong></a>:

  354. <a class="reference internal" href="#whatsnew311-pep670"><span class="std std-ref">Macros converted to static inline functions</span></a></p></li>

  355. </ul>

  356. </section>

  357. <section id="new-features">

  358. <span id="whatsnew311-features"></span><h2>New Features<a class="headerlink" href="#new-features" title="Link to this heading">¶</a></h2>

  359. <section id="pep-657-fine-grained-error-locations-in-tracebacks">

  360. <span id="whatsnew311-pep657"></span><h3>PEP 657: Fine-grained error locations in tracebacks<a class="headerlink" href="#pep-657-fine-grained-error-locations-in-tracebacks" title="Link to this heading">¶</a></h3>

  361. <p>When printing tracebacks, the interpreter will now point to the exact expression

  362. that caused the error, instead of just the line. For example:</p>

  363. <div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="n">Traceback</span> <span class="p">(</span><span class="n">most</span> <span class="n">recent</span> <span class="n">call</span> <span class="n">last</span><span class="p">):</span>

  364.   <span class="n">File</span> <span class="s2">&quot;distance.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">11</span><span class="p">,</span> <span class="ow">in</span> <span class="o">&lt;</span><span class="n">module</span><span class="o">&gt;</span>

  365.     <span class="nb">print</span><span class="p">(</span><span class="n">manhattan_distance</span><span class="p">(</span><span class="n">p1</span><span class="p">,</span> <span class="n">p2</span><span class="p">))</span>

  366.           <span class="o">^^^^^^^^^^^^^^^^^^^^^^^^^^</span>

  367.   <span class="n">File</span> <span class="s2">&quot;distance.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">6</span><span class="p">,</span> <span class="ow">in</span> <span class="n">manhattan_distance</span>

  368.     <span class="k">return</span> <span class="nb">abs</span><span class="p">(</span><span class="n">point_1</span><span class="o">.</span><span class="n">x</span> <span class="o">-</span> <span class="n">point_2</span><span class="o">.</span><span class="n">x</span><span class="p">)</span> <span class="o">+</span> <span class="nb">abs</span><span class="p">(</span><span class="n">point_1</span><span class="o">.</span><span class="n">y</span> <span class="o">-</span> <span class="n">point_2</span><span class="o">.</span><span class="n">y</span><span class="p">)</span>

  369.                            <span class="o">^^^^^^^^^</span>

  370. <span class="ne">AttributeError</span><span class="p">:</span> <span class="s1">&#39;NoneType&#39;</span> <span class="nb">object</span> <span class="n">has</span> <span class="n">no</span> <span class="n">attribute</span> <span class="s1">&#39;x&#39;</span>

  371. </pre></div>

  372. </div>

  373. <p>Previous versions of the interpreter would point to just the line, making it

  374. ambiguous which object was <code class="docutils literal notranslate"><span class="pre">None</span></code>. These enhanced errors can also be helpful

  375. when dealing with deeply nested <a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate"><span class="pre">dict</span></code></a> objects and multiple function calls:</p>

  376. <div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="n">Traceback</span> <span class="p">(</span><span class="n">most</span> <span class="n">recent</span> <span class="n">call</span> <span class="n">last</span><span class="p">):</span>

  377.   <span class="n">File</span> <span class="s2">&quot;query.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">37</span><span class="p">,</span> <span class="ow">in</span> <span class="o">&lt;</span><span class="n">module</span><span class="o">&gt;</span>

  378.     <span class="n">magic_arithmetic</span><span class="p">(</span><span class="s1">&#39;foo&#39;</span><span class="p">)</span>

  379.   <span class="n">File</span> <span class="s2">&quot;query.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">18</span><span class="p">,</span> <span class="ow">in</span> <span class="n">magic_arithmetic</span>

  380.     <span class="k">return</span> <span class="n">add_counts</span><span class="p">(</span><span class="n">x</span><span class="p">)</span> <span class="o">/</span> <span class="mi">25</span>

  381.            <span class="o">^^^^^^^^^^^^^</span>

  382.   <span class="n">File</span> <span class="s2">&quot;query.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">24</span><span class="p">,</span> <span class="ow">in</span> <span class="n">add_counts</span>

  383.     <span class="k">return</span> <span class="mi">25</span> <span class="o">+</span> <span class="n">query_user</span><span class="p">(</span><span class="n">user1</span><span class="p">)</span> <span class="o">+</span> <span class="n">query_user</span><span class="p">(</span><span class="n">user2</span><span class="p">)</span>

  384.                 <span class="o">^^^^^^^^^^^^^^^^^</span>

  385.   <span class="n">File</span> <span class="s2">&quot;query.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">32</span><span class="p">,</span> <span class="ow">in</span> <span class="n">query_user</span>

  386.     <span class="k">return</span> <span class="mi">1</span> <span class="o">+</span> <span class="n">query_count</span><span class="p">(</span><span class="n">db</span><span class="p">,</span> <span class="n">response</span><span class="p">[</span><span class="s1">&#39;a&#39;</span><span class="p">][</span><span class="s1">&#39;b&#39;</span><span class="p">][</span><span class="s1">&#39;c&#39;</span><span class="p">][</span><span class="s1">&#39;user&#39;</span><span class="p">],</span> <span class="n">retry</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>

  387.                                <span class="o">~~~~~~~~~~~~~~~~~~^^^^^</span>

  388. <span class="ne">TypeError</span><span class="p">:</span> <span class="s1">&#39;NoneType&#39;</span> <span class="nb">object</span> <span class="ow">is</span> <span class="ow">not</span> <span class="n">subscriptable</span>

  389. </pre></div>

  390. </div>

  391. <p>As well as complex arithmetic expressions:</p>

  392. <div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="n">Traceback</span> <span class="p">(</span><span class="n">most</span> <span class="n">recent</span> <span class="n">call</span> <span class="n">last</span><span class="p">):</span>

  393.   <span class="n">File</span> <span class="s2">&quot;calculation.py&quot;</span><span class="p">,</span> <span class="n">line</span> <span class="mi">54</span><span class="p">,</span> <span class="ow">in</span> <span class="o">&lt;</span><span class="n">module</span><span class="o">&gt;</span>

  394.     <span class="n">result</span> <span class="o">=</span> <span class="p">(</span><span class="n">x</span> <span class="o">/</span> <span class="n">y</span> <span class="o">/</span> <span class="n">z</span><span class="p">)</span> <span class="o">*</span> <span class="p">(</span><span class="n">a</span> <span class="o">/</span> <span class="n">b</span> <span class="o">/</span> <span class="n">c</span><span class="p">)</span>

  395.               <span class="o">~~~~~~^~~</span>

  396. <span class="ne">ZeroDivisionError</span><span class="p">:</span> <span class="n">division</span> <span class="n">by</span> <span class="n">zero</span>

  397. </pre></div>

  398. </div>

  399. <p>Additionally, the information used by the enhanced traceback feature

  400. is made available via a general API, that can be used to correlate

  401. <a class="reference internal" href="../glossary.html#term-bytecode"><span class="xref std std-term">bytecode</span></a> <a class="reference internal" href="../library/dis.html#bytecodes"><span class="std std-ref">instructions</span></a> with source code location.

  402. This information can be retrieved using:</p>

  403. <ul class="simple">

  404. <li><p>The <a class="reference internal" href="../reference/datamodel.html#codeobject.co_positions" title="codeobject.co_positions"><code class="xref py py-meth docutils literal notranslate"><span class="pre">codeobject.co_positions()</span></code></a> method in Python.</p></li>

  405. <li><p>The <a class="reference internal" href="../c-api/code.html#c.PyCode_Addr2Location" title="PyCode_Addr2Location"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_Addr2Location()</span></code></a> function in the C API.</p></li>

  406. </ul>

  407. <p>See <span class="target" id="index-5"></span><a class="pep reference external" href="https://peps.python.org/pep-0657/"><strong>PEP 657</strong></a> for more details. (Contributed by Pablo Galindo, Batuhan Taskaya

  408. and Ammar Askar in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43950">bpo-43950</a>.)</p>

  409. <div class="admonition note">

  410. <p class="admonition-title">Note</p>

  411. <p>This feature requires storing column positions in <a class="reference internal" href="../c-api/code.html#codeobjects"><span class="std std-ref">Code Objects</span></a>,

  412. which may result in a small increase in interpreter memory usage

  413. and disk usage for compiled Python files.

  414. To avoid storing the extra information

  415. and deactivate printing the extra traceback information,

  416. use the <a class="reference internal" href="../using/cmdline.html#cmdoption-X"><code class="xref std std-option docutils literal notranslate"><span class="pre">-X</span> <span class="pre">no_debug_ranges</span></code></a> command line option

  417. or the <span class="target" id="index-6"></span><a class="reference internal" href="../using/cmdline.html#envvar-PYTHONNODEBUGRANGES"><code class="xref std std-envvar docutils literal notranslate"><span class="pre">PYTHONNODEBUGRANGES</span></code></a> environment variable.</p>

  418. </div>

  419. </section>

  420. <section id="pep-654-exception-groups-and-except">

  421. <span id="whatsnew311-pep654"></span><h3>PEP 654: Exception Groups and <code class="docutils literal notranslate"><span class="pre">except*</span></code><a class="headerlink" href="#pep-654-exception-groups-and-except" title="Link to this heading">¶</a></h3>

  422. <p><span class="target" id="index-7"></span><a class="pep reference external" href="https://peps.python.org/pep-0654/"><strong>PEP 654</strong></a> introduces language features that enable a program

  423. to raise and handle multiple unrelated exceptions simultaneously.

  424. The builtin types <a class="reference internal" href="../library/exceptions.html#ExceptionGroup" title="ExceptionGroup"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ExceptionGroup</span></code></a> and <a class="reference internal" href="../library/exceptions.html#BaseExceptionGroup" title="BaseExceptionGroup"><code class="xref py py-exc docutils literal notranslate"><span class="pre">BaseExceptionGroup</span></code></a>

  425. make it possible to group exceptions and raise them together,

  426. and the new <a class="reference internal" href="../reference/compound_stmts.html#except-star"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">except*</span></code></a> syntax generalizes

  427. <a class="reference internal" href="../reference/compound_stmts.html#except"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">except</span></code></a> to match subgroups of exception groups.</p>

  428. <p>See <span class="target" id="index-8"></span><a class="pep reference external" href="https://peps.python.org/pep-0654/"><strong>PEP 654</strong></a> for more details.</p>

  429. <p>(Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45292">bpo-45292</a>. PEP written by

  430. Irit Katriel, Yury Selivanov and Guido van Rossum.)</p>

  431. </section>

  432. <section id="pep-678-exceptions-can-be-enriched-with-notes">

  433. <span id="whatsnew311-pep678"></span><h3>PEP 678: Exceptions can be enriched with notes<a class="headerlink" href="#pep-678-exceptions-can-be-enriched-with-notes" title="Link to this heading">¶</a></h3>

  434. <p>The <a class="reference internal" href="../library/exceptions.html#BaseException.add_note" title="BaseException.add_note"><code class="xref py py-meth docutils literal notranslate"><span class="pre">add_note()</span></code></a> method is added to <a class="reference internal" href="../library/exceptions.html#BaseException" title="BaseException"><code class="xref py py-exc docutils literal notranslate"><span class="pre">BaseException</span></code></a>.

  435. It can be used to enrich exceptions with context information

  436. that is not available at the time when the exception is raised.

  437. The added notes appear in the default traceback.</p>

  438. <p>See <span class="target" id="index-9"></span><a class="pep reference external" href="https://peps.python.org/pep-0678/"><strong>PEP 678</strong></a> for more details.</p>

  439. <p>(Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45607">bpo-45607</a>.

  440. PEP written by Zac Hatfield-Dodds.)</p>

  441. </section>

  442. <section id="windows-py-exe-launcher-improvements">

  443. <span id="whatsnew311-windows-launcher"></span><h3>Windows <code class="docutils literal notranslate"><span class="pre">py.exe</span></code> launcher improvements<a class="headerlink" href="#windows-py-exe-launcher-improvements" title="Link to this heading">¶</a></h3>

  444. <p>The copy of the <a class="reference internal" href="../using/windows.html#launcher"><span class="std std-ref">Python Launcher for Windows</span></a> included with Python 3.11 has been significantly

  445. updated. It now supports company/tag syntax as defined in <span class="target" id="index-10"></span><a class="pep reference external" href="https://peps.python.org/pep-0514/"><strong>PEP 514</strong></a> using the

  446. <code class="samp docutils literal notranslate"><span class="pre">-V:</span><em><span class="pre">&lt;company&gt;</span></em><span class="pre">/</span><em><span class="pre">&lt;tag&gt;</span></em></code> argument instead of the limited <code class="samp docutils literal notranslate"><span class="pre">-</span><em><span class="pre">&lt;major&gt;</span></em><span class="pre">.</span><em><span class="pre">&lt;minor&gt;</span></em></code>.

  447. This allows launching distributions other than <code class="docutils literal notranslate"><span class="pre">PythonCore</span></code>,

  448. the one hosted on <a class="reference external" href="https://www.python.org">python.org</a>.</p>

  449. <p>When using <code class="docutils literal notranslate"><span class="pre">-V:</span></code> selectors, either company or tag can be omitted, but all

  450. installs will be searched. For example, <code class="docutils literal notranslate"><span class="pre">-V:OtherPython/</span></code> will select the

  451. “best” tag registered for <code class="docutils literal notranslate"><span class="pre">OtherPython</span></code>, while <code class="docutils literal notranslate"><span class="pre">-V:3.11</span></code> or <code class="docutils literal notranslate"><span class="pre">-V:/3.11</span></code>

  452. will select the “best” distribution with tag <code class="docutils literal notranslate"><span class="pre">3.11</span></code>.</p>

  453. <p>When using the legacy <code class="samp docutils literal notranslate"><span class="pre">-</span><em><span class="pre">&lt;major&gt;</span></em></code>, <code class="samp docutils literal notranslate"><span class="pre">-</span><em><span class="pre">&lt;major&gt;</span></em><span class="pre">.</span><em><span class="pre">&lt;minor&gt;</span></em></code>,

  454. <code class="samp docutils literal notranslate"><span class="pre">-</span><em><span class="pre">&lt;major&gt;</span></em><span class="pre">-</span><em><span class="pre">&lt;bitness&gt;</span></em></code> or <code class="samp docutils literal notranslate"><span class="pre">-</span><em><span class="pre">&lt;major&gt;</span></em><span class="pre">.</span><em><span class="pre">&lt;minor&gt;</span></em><span class="pre">-</span><em><span class="pre">&lt;bitness&gt;</span></em></code> arguments,

  455. all existing behaviour should be preserved from past versions,

  456. and only releases from <code class="docutils literal notranslate"><span class="pre">PythonCore</span></code> will be selected.

  457. However, the <code class="docutils literal notranslate"><span class="pre">-64</span></code> suffix now implies “not 32-bit” (not necessarily x86-64),

  458. as there are multiple supported 64-bit platforms.

  459. 32-bit runtimes are detected by checking the runtime’s tag for a <code class="docutils literal notranslate"><span class="pre">-32</span></code> suffix.

  460. All releases of Python since 3.5 have included this in their 32-bit builds.</p>

  461. </section>

  462. </section>

  463. <section id="new-features-related-to-type-hints">

  464. <span id="whatsnew311-typing-features"></span><span id="new-feat-related-type-hints-311"></span><h2>New Features Related to Type Hints<a class="headerlink" href="#new-features-related-to-type-hints" title="Link to this heading">¶</a></h2>

  465. <p>This section covers major changes affecting <span class="target" id="index-11"></span><a class="pep reference external" href="https://peps.python.org/pep-0484/"><strong>PEP 484</strong></a> type hints and

  466. the <a class="reference internal" href="../library/typing.html#module-typing" title="typing: Support for type hints (see :pep:`484`)."><code class="xref py py-mod docutils literal notranslate"><span class="pre">typing</span></code></a> module.</p>

  467. <section id="pep-646-variadic-generics">

  468. <span id="whatsnew311-pep646"></span><h3>PEP 646: Variadic generics<a class="headerlink" href="#pep-646-variadic-generics" title="Link to this heading">¶</a></h3>

  469. <p><span class="target" id="index-12"></span><a class="pep reference external" href="https://peps.python.org/pep-0484/"><strong>PEP 484</strong></a> previously introduced <a class="reference internal" href="../library/typing.html#typing.TypeVar" title="typing.TypeVar"><code class="xref py py-data docutils literal notranslate"><span class="pre">TypeVar</span></code></a>, enabling creation

  470. of generics parameterised with a single type. <span class="target" id="index-13"></span><a class="pep reference external" href="https://peps.python.org/pep-0646/"><strong>PEP 646</strong></a> adds

  471. <a class="reference internal" href="../library/typing.html#typing.TypeVarTuple" title="typing.TypeVarTuple"><code class="xref py py-data docutils literal notranslate"><span class="pre">TypeVarTuple</span></code></a>, enabling parameterisation

  472. with an <em>arbitrary</em> number of types. In other words,

  473. a <a class="reference internal" href="../library/typing.html#typing.TypeVarTuple" title="typing.TypeVarTuple"><code class="xref py py-data docutils literal notranslate"><span class="pre">TypeVarTuple</span></code></a> is a <em>variadic</em> type variable,

  474. enabling <em>variadic</em> generics.</p>

  475. <p>This enables a wide variety of use cases.

  476. In particular, it allows the type of array-like structures

  477. in numerical computing libraries such as NumPy and TensorFlow to be

  478. parameterised with the array <em>shape</em>. Static type checkers will now

  479. be able to catch shape-related bugs in code that uses these libraries.</p>

  480. <p>See <span class="target" id="index-14"></span><a class="pep reference external" href="https://peps.python.org/pep-0646/"><strong>PEP 646</strong></a> for more details.</p>

  481. <p>(Contributed by Matthew Rahtz in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43224">bpo-43224</a>, with contributions by

  482. Serhiy Storchaka and Jelle Zijlstra. PEP written by Mark Mendoza, Matthew

  483. Rahtz, Pradeep Kumar Srinivasan, and Vincent Siles.)</p>

  484. </section>

  485. <section id="pep-655-marking-individual-typeddict-items-as-required-or-not-required">

  486. <span id="whatsnew311-pep655"></span><h3>PEP 655: Marking individual <code class="docutils literal notranslate"><span class="pre">TypedDict</span></code> items as required or not-required<a class="headerlink" href="#pep-655-marking-individual-typeddict-items-as-required-or-not-required" title="Link to this heading">¶</a></h3>

  487. <p><a class="reference internal" href="../library/typing.html#typing.Required" title="typing.Required"><code class="xref py py-data docutils literal notranslate"><span class="pre">Required</span></code></a> and <a class="reference internal" href="../library/typing.html#typing.NotRequired" title="typing.NotRequired"><code class="xref py py-data docutils literal notranslate"><span class="pre">NotRequired</span></code></a> provide a

  488. straightforward way to mark whether individual items in a

  489. <a class="reference internal" href="../library/typing.html#typing.TypedDict" title="typing.TypedDict"><code class="xref py py-class docutils literal notranslate"><span class="pre">TypedDict</span></code></a> must be present. Previously, this was only possible

  490. using inheritance.</p>

  491. <p>All fields are still required by default,

  492. unless the <em>total</em> parameter is set to <code class="docutils literal notranslate"><span class="pre">False</span></code>,

  493. in which case all fields are still not-required by default.

  494. For example, the following specifies a <code class="xref py py-class docutils literal notranslate"><span class="pre">TypedDict</span></code>

  495. with one required and one not-required key:</p>

  496. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">Movie</span><span class="p">(</span><span class="n">TypedDict</span><span class="p">):</span>

  497.    <span class="n">title</span><span class="p">:</span> <span class="nb">str</span>

  498.    <span class="n">year</span><span class="p">:</span> <span class="n">NotRequired</span><span class="p">[</span><span class="nb">int</span><span class="p">]</span>

  499. 

  500. <span class="n">m1</span><span class="p">:</span> <span class="n">Movie</span> <span class="o">=</span> <span class="p">{</span><span class="s2">&quot;title&quot;</span><span class="p">:</span> <span class="s2">&quot;Black Panther&quot;</span><span class="p">,</span> <span class="s2">&quot;year&quot;</span><span class="p">:</span> <span class="mi">2018</span><span class="p">}</span>  <span class="c1"># OK</span>

  501. <span class="n">m2</span><span class="p">:</span> <span class="n">Movie</span> <span class="o">=</span> <span class="p">{</span><span class="s2">&quot;title&quot;</span><span class="p">:</span> <span class="s2">&quot;Star Wars&quot;</span><span class="p">}</span>  <span class="c1"># OK (year is not required)</span>

  502. <span class="n">m3</span><span class="p">:</span> <span class="n">Movie</span> <span class="o">=</span> <span class="p">{</span><span class="s2">&quot;year&quot;</span><span class="p">:</span> <span class="mi">2022</span><span class="p">}</span>  <span class="c1"># ERROR (missing required field title)</span>

  503. </pre></div>

  504. </div>

  505. <p>The following definition is equivalent:</p>

  506. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">Movie</span><span class="p">(</span><span class="n">TypedDict</span><span class="p">,</span> <span class="n">total</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span>

  507.    <span class="n">title</span><span class="p">:</span> <span class="n">Required</span><span class="p">[</span><span class="nb">str</span><span class="p">]</span>

  508.    <span class="n">year</span><span class="p">:</span> <span class="nb">int</span>

  509. </pre></div>

  510. </div>

  511. <p>See <span class="target" id="index-15"></span><a class="pep reference external" href="https://peps.python.org/pep-0655/"><strong>PEP 655</strong></a> for more details.</p>

  512. <p>(Contributed by David Foster and Jelle Zijlstra in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47087">bpo-47087</a>. PEP

  513. written by David Foster.)</p>

  514. </section>

  515. <section id="pep-673-self-type">

  516. <span id="whatsnew311-pep673"></span><h3>PEP 673: <code class="docutils literal notranslate"><span class="pre">Self</span></code> type<a class="headerlink" href="#pep-673-self-type" title="Link to this heading">¶</a></h3>

  517. <p>The new <a class="reference internal" href="../library/typing.html#typing.Self" title="typing.Self"><code class="xref py py-data docutils literal notranslate"><span class="pre">Self</span></code></a> annotation provides a simple and intuitive

  518. way to annotate methods that return an instance of their class. This

  519. behaves the same as the <a class="reference internal" href="../library/typing.html#typing.TypeVar" title="typing.TypeVar"><code class="xref py py-class docutils literal notranslate"><span class="pre">TypeVar</span></code></a>-based approach

  520. <span class="target" id="index-16"></span><a class="pep reference external" href="https://peps.python.org/pep-0484/#annotating-instance-and-class-methods"><strong>specified in PEP 484</strong></a>,

  521. but is more concise and easier to follow.</p>

  522. <p>Common use cases include alternative constructors provided as

  523. <a class="reference internal" href="../library/functions.html#classmethod" title="classmethod"><code class="xref py py-func docutils literal notranslate"><span class="pre">classmethod</span></code></a>s,

  524. and <a class="reference internal" href="../reference/datamodel.html#object.__enter__" title="object.__enter__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__enter__()</span></code></a> methods that return <code class="docutils literal notranslate"><span class="pre">self</span></code>:</p>

  525. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">MyLock</span><span class="p">:</span>

  526.     <span class="k">def</span> <span class="fm">__enter__</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">Self</span><span class="p">:</span>

  527.         <span class="bp">self</span><span class="o">.</span><span class="n">lock</span><span class="p">()</span>

  528.         <span class="k">return</span> <span class="bp">self</span>

  529. 

  530.     <span class="o">...</span>

  531. 

  532. <span class="k">class</span> <span class="nc">MyInt</span><span class="p">:</span>

  533.     <span class="nd">@classmethod</span>

  534.     <span class="k">def</span> <span class="nf">fromhex</span><span class="p">(</span><span class="bp">cls</span><span class="p">,</span> <span class="n">s</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">Self</span><span class="p">:</span>

  535.         <span class="k">return</span> <span class="bp">cls</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="n">s</span><span class="p">,</span> <span class="mi">16</span><span class="p">))</span>

  536. 

  537.     <span class="o">...</span>

  538. </pre></div>

  539. </div>

  540. <p><a class="reference internal" href="../library/typing.html#typing.Self" title="typing.Self"><code class="xref py py-data docutils literal notranslate"><span class="pre">Self</span></code></a> can also be used to annotate method parameters

  541. or attributes of the same type as their enclosing class.</p>

  542. <p>See <span class="target" id="index-17"></span><a class="pep reference external" href="https://peps.python.org/pep-0673/"><strong>PEP 673</strong></a> for more details.</p>

  543. <p>(Contributed by James Hilton-Balfe in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46534">bpo-46534</a>. PEP written by

  544. Pradeep Kumar Srinivasan and James Hilton-Balfe.)</p>

  545. </section>

  546. <section id="pep-675-arbitrary-literal-string-type">

  547. <span id="whatsnew311-pep675"></span><h3>PEP 675: Arbitrary literal string type<a class="headerlink" href="#pep-675-arbitrary-literal-string-type" title="Link to this heading">¶</a></h3>

  548. <p>The new <a class="reference internal" href="../library/typing.html#typing.LiteralString" title="typing.LiteralString"><code class="xref py py-data docutils literal notranslate"><span class="pre">LiteralString</span></code></a> annotation may be used to indicate

  549. that a function parameter can be of any literal string type. This allows

  550. a function to accept arbitrary literal string types, as well as strings

  551. created from other literal strings. Type checkers can then

  552. enforce that sensitive functions, such as those that execute SQL

  553. statements or shell commands, are called only with static arguments,

  554. providing protection against injection attacks.</p>

  555. <p>For example, a SQL query function could be annotated as follows:</p>

  556. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">def</span> <span class="nf">run_query</span><span class="p">(</span><span class="n">sql</span><span class="p">:</span> <span class="n">LiteralString</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="o">...</span>

  557.     <span class="o">...</span>

  558. 

  559. <span class="k">def</span> <span class="nf">caller</span><span class="p">(</span>

  560.     <span class="n">arbitrary_string</span><span class="p">:</span> <span class="nb">str</span><span class="p">,</span>

  561.     <span class="n">query_string</span><span class="p">:</span> <span class="n">LiteralString</span><span class="p">,</span>

  562.     <span class="n">table_name</span><span class="p">:</span> <span class="n">LiteralString</span><span class="p">,</span>

  563. <span class="p">)</span> <span class="o">-&gt;</span> <span class="kc">None</span><span class="p">:</span>

  564.     <span class="n">run_query</span><span class="p">(</span><span class="s2">&quot;SELECT * FROM students&quot;</span><span class="p">)</span>       <span class="c1"># ok</span>

  565.     <span class="n">run_query</span><span class="p">(</span><span class="n">query_string</span><span class="p">)</span>                   <span class="c1"># ok</span>

  566.     <span class="n">run_query</span><span class="p">(</span><span class="s2">&quot;SELECT * FROM &quot;</span> <span class="o">+</span> <span class="n">table_name</span><span class="p">)</span>  <span class="c1"># ok</span>

  567.     <span class="n">run_query</span><span class="p">(</span><span class="n">arbitrary_string</span><span class="p">)</span>               <span class="c1"># type checker error</span>

  568.     <span class="n">run_query</span><span class="p">(</span>                                <span class="c1"># type checker error</span>

  569.         <span class="sa">f</span><span class="s2">&quot;SELECT * FROM students WHERE name = </span><span class="si">{</span><span class="n">arbitrary_string</span><span class="si">}</span><span class="s2">&quot;</span>

  570.     <span class="p">)</span>

  571. </pre></div>

  572. </div>

  573. <p>See <span class="target" id="index-18"></span><a class="pep reference external" href="https://peps.python.org/pep-0675/"><strong>PEP 675</strong></a> for more details.</p>

  574. <p>(Contributed by Jelle Zijlstra in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47088">bpo-47088</a>. PEP written by Pradeep

  575. Kumar Srinivasan and Graham Bleaney.)</p>

  576. </section>

  577. <section id="pep-681-data-class-transforms">

  578. <span id="whatsnew311-pep681"></span><h3>PEP 681: Data class transforms<a class="headerlink" href="#pep-681-data-class-transforms" title="Link to this heading">¶</a></h3>

  579. <p><a class="reference internal" href="../library/typing.html#typing.dataclass_transform" title="typing.dataclass_transform"><code class="xref py py-data docutils literal notranslate"><span class="pre">dataclass_transform</span></code></a> may be used to

  580. decorate a class, metaclass, or a function that is itself a decorator.

  581. The presence of <code class="docutils literal notranslate"><span class="pre">&#64;dataclass_transform()</span></code> tells a static type checker that the

  582. decorated object performs runtime “magic” that transforms a class,

  583. giving it <a class="reference internal" href="../library/dataclasses.html#dataclasses.dataclass" title="dataclasses.dataclass"><code class="xref py py-func docutils literal notranslate"><span class="pre">dataclass</span></code></a>-like behaviors.</p>

  584. <p>For example:</p>

  585. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1"># The create_model decorator is defined by a library.</span>

  586. <span class="nd">@typing</span><span class="o">.</span><span class="n">dataclass_transform</span><span class="p">()</span>

  587. <span class="k">def</span> <span class="nf">create_model</span><span class="p">(</span><span class="bp">cls</span><span class="p">:</span> <span class="n">Type</span><span class="p">[</span><span class="n">T</span><span class="p">])</span> <span class="o">-&gt;</span> <span class="n">Type</span><span class="p">[</span><span class="n">T</span><span class="p">]:</span>

  588.     <span class="bp">cls</span><span class="o">.</span><span class="fm">__init__</span> <span class="o">=</span> <span class="o">...</span>

  589.     <span class="bp">cls</span><span class="o">.</span><span class="fm">__eq__</span> <span class="o">=</span> <span class="o">...</span>

  590.     <span class="bp">cls</span><span class="o">.</span><span class="fm">__ne__</span> <span class="o">=</span> <span class="o">...</span>

  591.     <span class="k">return</span> <span class="bp">cls</span>

  592. 

  593. <span class="c1"># The create_model decorator can now be used to create new model classes:</span>

  594. <span class="nd">@create_model</span>

  595. <span class="k">class</span> <span class="nc">CustomerModel</span><span class="p">:</span>

  596.     <span class="nb">id</span><span class="p">:</span> <span class="nb">int</span>

  597.     <span class="n">name</span><span class="p">:</span> <span class="nb">str</span>

  598. 

  599. <span class="n">c</span> <span class="o">=</span> <span class="n">CustomerModel</span><span class="p">(</span><span class="nb">id</span><span class="o">=</span><span class="mi">327</span><span class="p">,</span> <span class="n">name</span><span class="o">=</span><span class="s2">&quot;Eric Idle&quot;</span><span class="p">)</span>

  600. </pre></div>

  601. </div>

  602. <p>See <span class="target" id="index-19"></span><a class="pep reference external" href="https://peps.python.org/pep-0681/"><strong>PEP 681</strong></a> for more details.</p>

  603. <p>(Contributed by Jelle Zijlstra in <a class="reference external" href="https://github.com/python/cpython/issues/91860">gh-91860</a>. PEP written by

  604. Erik De Bonte and Eric Traut.)</p>

  605. </section>

  606. <section id="pep-563-may-not-be-the-future">

  607. <span id="whatsnew311-pep563-deferred"></span><h3>PEP 563 may not be the future<a class="headerlink" href="#pep-563-may-not-be-the-future" title="Link to this heading">¶</a></h3>

  608. <p><span class="target" id="index-20"></span><a class="pep reference external" href="https://peps.python.org/pep-0563/"><strong>PEP 563</strong></a> Postponed Evaluation of Annotations

  609. (the <code class="docutils literal notranslate"><span class="pre">from</span> <span class="pre">__future__</span> <span class="pre">import</span> <span class="pre">annotations</span></code> <a class="reference internal" href="../reference/simple_stmts.html#future"><span class="std std-ref">future statement</span></a>)

  610. that was originally planned for release in Python 3.10

  611. has been put on hold indefinitely.

  612. See <a class="reference external" href="https://mail.python.org/archives/list/python-dev&#64;python.org/message/VIZEBX5EYMSYIJNDBF6DMUMZOCWHARSO/">this message from the Steering Council</a>

  613. for more information.</p>

  614. </section>

  615. </section>

  616. <section id="other-language-changes">

  617. <span id="whatsnew311-other-lang-changes"></span><h2>Other Language Changes<a class="headerlink" href="#other-language-changes" title="Link to this heading">¶</a></h2>

  618. <ul class="simple">

  619. <li><p>Starred unpacking expressions can now be used in <a class="reference internal" href="../reference/compound_stmts.html#for"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">for</span></code></a> statements.

  620. (See <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46725">bpo-46725</a> for more details.)</p></li>

  621. <li><p>Asynchronous <a class="reference internal" href="../reference/expressions.html#comprehensions"><span class="std std-ref">comprehensions</span></a> are now allowed

  622. inside comprehensions in <a class="reference internal" href="../reference/compound_stmts.html#async-def"><span class="std std-ref">asynchronous functions</span></a>.

  623. Outer comprehensions implicitly become asynchronous in this case.

  624. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=33346">bpo-33346</a>.)</p></li>

  625. <li><p>A <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> is now raised instead of an <a class="reference internal" href="../library/exceptions.html#AttributeError" title="AttributeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AttributeError</span></code></a> in

  626. <a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> statements and <a class="reference internal" href="../library/contextlib.html#contextlib.ExitStack.enter_context" title="contextlib.ExitStack.enter_context"><code class="xref py py-meth docutils literal notranslate"><span class="pre">contextlib.ExitStack.enter_context()</span></code></a>

  627. for objects that do not support the <a class="reference internal" href="../glossary.html#term-context-manager"><span class="xref std std-term">context manager</span></a> protocol,

  628. and in <a class="reference internal" href="../reference/compound_stmts.html#async-with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">async</span> <span class="pre">with</span></code></a> statements and

  629. <a class="reference internal" href="../library/contextlib.html#contextlib.AsyncExitStack.enter_async_context" title="contextlib.AsyncExitStack.enter_async_context"><code class="xref py py-meth docutils literal notranslate"><span class="pre">contextlib.AsyncExitStack.enter_async_context()</span></code></a>

  630. for objects not supporting the <a class="reference internal" href="../glossary.html#term-asynchronous-context-manager"><span class="xref std std-term">asynchronous context manager</span></a> protocol.

  631. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=12022">bpo-12022</a> and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44471">bpo-44471</a>.)</p></li>

  632. <li><p>Added <a class="reference internal" href="../library/pickle.html#object.__getstate__" title="object.__getstate__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">object.__getstate__()</span></code></a>, which provides the default

  633. implementation of the <code class="xref py py-meth docutils literal notranslate"><span class="pre">__getstate__()</span></code> method. <a class="reference internal" href="../library/copy.html#module-copy" title="copy: Shallow and deep copy operations."><code class="xref py py-mod docutils literal notranslate"><span class="pre">copy</span></code></a>ing

  634. and <a class="reference internal" href="../library/pickle.html#module-pickle" title="pickle: Convert Python objects to streams of bytes and back."><code class="xref py py-mod docutils literal notranslate"><span class="pre">pickle</span></code></a>ing instances of subclasses of builtin types

  635. <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytearray</span></code></a>, <a class="reference internal" href="../library/stdtypes.html#set" title="set"><code class="xref py py-class docutils literal notranslate"><span class="pre">set</span></code></a>, <a class="reference internal" href="../library/stdtypes.html#frozenset" title="frozenset"><code class="xref py py-class docutils literal notranslate"><span class="pre">frozenset</span></code></a>,

  636. <a class="reference internal" href="../library/collections.html#collections.OrderedDict" title="collections.OrderedDict"><code class="xref py py-class docutils literal notranslate"><span class="pre">collections.OrderedDict</span></code></a>, <a class="reference internal" href="../library/collections.html#collections.deque" title="collections.deque"><code class="xref py py-class docutils literal notranslate"><span class="pre">collections.deque</span></code></a>,

  637. <a class="reference internal" href="../library/weakref.html#weakref.WeakSet" title="weakref.WeakSet"><code class="xref py py-class docutils literal notranslate"><span class="pre">weakref.WeakSet</span></code></a>, and <a class="reference internal" href="../library/datetime.html#datetime.tzinfo" title="datetime.tzinfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">datetime.tzinfo</span></code></a> now copies and

  638. pickles instance attributes implemented as <a class="reference internal" href="../glossary.html#term-__slots__"><span class="xref std std-term">slots</span></a>.

  639. This change has an unintended side effect: It trips up a small minority

  640. of existing Python projects not expecting <a class="reference internal" href="../library/pickle.html#object.__getstate__" title="object.__getstate__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">object.__getstate__()</span></code></a> to

  641. exist. See the later comments on <a class="reference external" href="https://github.com/python/cpython/issues/70766">gh-70766</a> for discussions of what

  642. workarounds such code may need.

  643. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=26579">bpo-26579</a>.)</p></li>

  644. </ul>

  645. <ul class="simple" id="whatsnew311-pythonsafepath">

  646. <li><p>Added a <a class="reference internal" href="../using/cmdline.html#cmdoption-P"><code class="xref std std-option docutils literal notranslate"><span class="pre">-P</span></code></a> command line option

  647. and a <span class="target" id="index-21"></span><a class="reference internal" href="../using/cmdline.html#envvar-PYTHONSAFEPATH"><code class="xref std std-envvar docutils literal notranslate"><span class="pre">PYTHONSAFEPATH</span></code></a> environment variable,

  648. which disable the automatic prepending to <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a>

  649. of the script’s directory when running a script,

  650. or the current directory when using <a class="reference internal" href="../using/cmdline.html#cmdoption-c"><code class="xref std std-option docutils literal notranslate"><span class="pre">-c</span></code></a> and <a class="reference internal" href="../using/cmdline.html#cmdoption-m"><code class="xref std std-option docutils literal notranslate"><span class="pre">-m</span></code></a>.

  651. This ensures only stdlib and installed modules

  652. are picked up by <a class="reference internal" href="../reference/simple_stmts.html#import"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">import</span></code></a>,

  653. and avoids unintentionally or maliciously shadowing modules

  654. with those in a local (and typically user-writable) directory.

  655. (Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/57684">gh-57684</a>.)</p></li>

  656. <li><p>A <code class="docutils literal notranslate"><span class="pre">&quot;z&quot;</span></code> option was added to the <a class="reference internal" href="../library/string.html#formatspec"><span class="std std-ref">Format Specification Mini-Language</span></a> that

  657. coerces negative to positive zero after rounding to the format precision.

  658. See <span class="target" id="index-22"></span><a class="pep reference external" href="https://peps.python.org/pep-0682/"><strong>PEP 682</strong></a> for more details.

  659. (Contributed by John Belmonte in <a class="reference external" href="https://github.com/python/cpython/issues/90153">gh-90153</a>.)</p></li>

  660. <li><p>Bytes are no longer accepted on <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a>.  Support broke sometime

  661. between Python 3.2 and 3.6, with no one noticing until after Python 3.10.0

  662. was released. In addition, bringing back support would be problematic due to

  663. interactions between <a class="reference internal" href="../using/cmdline.html#cmdoption-b"><code class="xref std std-option docutils literal notranslate"><span class="pre">-b</span></code></a> and <a class="reference internal" href="../library/sys.html#sys.path_importer_cache" title="sys.path_importer_cache"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path_importer_cache</span></code></a> when

  664. there is a mixture of <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a> and <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytes</span></code></a> keys.

  665. (Contributed by Thomas Grainger in <a class="reference external" href="https://github.com/python/cpython/issues/91181">gh-91181</a>.)</p></li>

  666. </ul>

  667. </section>

  668. <section id="other-cpython-implementation-changes">

  669. <span id="whatsnew311-other-implementation-changes"></span><h2>Other CPython Implementation Changes<a class="headerlink" href="#other-cpython-implementation-changes" title="Link to this heading">¶</a></h2>

  670. <ul class="simple">

  671. <li><p>The special methods <a class="reference internal" href="../reference/datamodel.html#object.__complex__" title="object.__complex__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__complex__()</span></code></a> for <a class="reference internal" href="../library/functions.html#complex" title="complex"><code class="xref py py-class docutils literal notranslate"><span class="pre">complex</span></code></a>

  672. and <a class="reference internal" href="../reference/datamodel.html#object.__bytes__" title="object.__bytes__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__bytes__()</span></code></a> for <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytes</span></code></a> are implemented to support

  673. the <a class="reference internal" href="../library/typing.html#typing.SupportsComplex" title="typing.SupportsComplex"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.SupportsComplex</span></code></a> and <a class="reference internal" href="../library/typing.html#typing.SupportsBytes" title="typing.SupportsBytes"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.SupportsBytes</span></code></a> protocols.

  674. (Contributed by Mark Dickinson and Donghee Na in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=24234">bpo-24234</a>.)</p></li>

  675. <li><p><code class="docutils literal notranslate"><span class="pre">siphash13</span></code> is added as a new internal hashing algorithm.

  676. It has similar security properties as <code class="docutils literal notranslate"><span class="pre">siphash24</span></code>,

  677. but it is slightly faster for long inputs.

  678. <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a>, <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytes</span></code></a>, and some other types

  679. now use it as the default algorithm for <a class="reference internal" href="../library/functions.html#hash" title="hash"><code class="xref py py-func docutils literal notranslate"><span class="pre">hash()</span></code></a>.

  680. <span class="target" id="index-23"></span><a class="pep reference external" href="https://peps.python.org/pep-0552/"><strong>PEP 552</strong></a> <a class="reference internal" href="../reference/import.html#pyc-invalidation"><span class="std std-ref">hash-based .pyc files</span></a>

  681. now use <code class="docutils literal notranslate"><span class="pre">siphash13</span></code> too.

  682. (Contributed by Inada Naoki in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=29410">bpo-29410</a>.)</p></li>

  683. <li><p>When an active exception is re-raised by a <a class="reference internal" href="../reference/simple_stmts.html#raise"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">raise</span></code></a> statement with no parameters,

  684. the traceback attached to this exception is now always <code class="docutils literal notranslate"><span class="pre">sys.exc_info()[1].__traceback__</span></code>.

  685. This means that changes made to the traceback in the current <a class="reference internal" href="../reference/compound_stmts.html#except"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">except</span></code></a> clause are

  686. reflected in the re-raised exception.

  687. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45711">bpo-45711</a>.)</p></li>

  688. <li><p>The interpreter state’s representation of handled exceptions

  689. (aka <code class="docutils literal notranslate"><span class="pre">exc_info</span></code> or <code class="docutils literal notranslate"><span class="pre">_PyErr_StackItem</span></code>)

  690. now only has the <code class="docutils literal notranslate"><span class="pre">exc_value</span></code> field; <code class="docutils literal notranslate"><span class="pre">exc_type</span></code> and <code class="docutils literal notranslate"><span class="pre">exc_traceback</span></code>

  691. have been removed, as they can be derived from <code class="docutils literal notranslate"><span class="pre">exc_value</span></code>.

  692. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45711">bpo-45711</a>.)</p></li>

  693. <li><p>A new <a class="reference internal" href="../using/windows.html#install-quiet-option"><span class="std std-ref">command line option</span></a>, <code class="docutils literal notranslate"><span class="pre">AppendPath</span></code>,

  694. has been added for the Windows installer.

  695. It behaves similarly to <code class="docutils literal notranslate"><span class="pre">PrependPath</span></code>,

  696. but appends the install and scripts directories instead of prepending them.

  697. (Contributed by Bastian Neuburger in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44934">bpo-44934</a>.)</p></li>

  698. <li><p>The <a class="reference internal" href="../c-api/init_config.html#c.PyConfig.module_search_paths_set" title="PyConfig.module_search_paths_set"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyConfig.module_search_paths_set</span></code></a> field must now be set to <code class="docutils literal notranslate"><span class="pre">1</span></code> for

  699. initialization to use <a class="reference internal" href="../c-api/init_config.html#c.PyConfig.module_search_paths" title="PyConfig.module_search_paths"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyConfig.module_search_paths</span></code></a> to initialize

  700. <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a>. Otherwise, initialization will recalculate the path and replace

  701. any values added to <code class="docutils literal notranslate"><span class="pre">module_search_paths</span></code>.</p></li>

  702. <li><p>The output of the <a class="reference internal" href="../using/cmdline.html#cmdoption-help"><code class="xref std std-option docutils literal notranslate"><span class="pre">--help</span></code></a> option now fits in 50 lines/80 columns.

  703. Information about <a class="reference internal" href="../using/cmdline.html#using-on-envvars"><span class="std std-ref">Python environment variables</span></a>

  704. and <a class="reference internal" href="../using/cmdline.html#cmdoption-X"><code class="xref std std-option docutils literal notranslate"><span class="pre">-X</span></code></a> options is now available using the respective

  705. <a class="reference internal" href="../using/cmdline.html#cmdoption-help-env"><code class="xref std std-option docutils literal notranslate"><span class="pre">--help-env</span></code></a> and <a class="reference internal" href="../using/cmdline.html#cmdoption-help-xoptions"><code class="xref std std-option docutils literal notranslate"><span class="pre">--help-xoptions</span></code></a> flags,

  706. and with the new <a class="reference internal" href="../using/cmdline.html#cmdoption-help-all"><code class="xref std std-option docutils literal notranslate"><span class="pre">--help-all</span></code></a>.

  707. (Contributed by Éric Araujo in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46142">bpo-46142</a>.)</p></li>

  708. <li><p>Converting between <a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate"><span class="pre">int</span></code></a> and <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a> in bases other than 2

  709. (binary), 4, 8 (octal), 16 (hexadecimal), or 32 such as base 10 (decimal)

  710. now raises a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> if the number of digits in string form is

  711. above a limit to avoid potential denial of service attacks due to the

  712. algorithmic complexity. This is a mitigation for <a class="reference external" href="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10735">CVE-2020-10735</a>.

  713. This limit can be configured or disabled by environment variable, command

  714. line flag, or <a class="reference internal" href="../library/sys.html#module-sys" title="sys: Access system-specific parameters and functions."><code class="xref py py-mod docutils literal notranslate"><span class="pre">sys</span></code></a> APIs. See the <a class="reference internal" href="../library/stdtypes.html#int-max-str-digits"><span class="std std-ref">integer string conversion

  715. length limitation</span></a> documentation.  The default limit

  716. is 4300 digits in string form.</p></li>

  717. </ul>

  718. </section>

  719. <section id="new-modules">

  720. <span id="whatsnew311-new-modules"></span><h2>New Modules<a class="headerlink" href="#new-modules" title="Link to this heading">¶</a></h2>

  721. <ul class="simple">

  722. <li><p><a class="reference internal" href="../library/tomllib.html#module-tomllib" title="tomllib: Parse TOML files."><code class="xref py py-mod docutils literal notranslate"><span class="pre">tomllib</span></code></a>: For parsing <a class="reference external" href="https://toml.io/">TOML</a>.

  723. See <span class="target" id="index-24"></span><a class="pep reference external" href="https://peps.python.org/pep-0680/"><strong>PEP 680</strong></a> for more details.

  724. (Contributed by Taneli Hukkinen in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40059">bpo-40059</a>.)</p></li>

  725. <li><p><a class="reference internal" href="../library/wsgiref.html#module-wsgiref.types" title="wsgiref.types: WSGI types for static type checking"><code class="xref py py-mod docutils literal notranslate"><span class="pre">wsgiref.types</span></code></a>:

  726. <span class="target" id="index-25"></span><a class="pep reference external" href="https://peps.python.org/pep-3333/"><strong>WSGI</strong></a>-specific types for static type checking.

  727. (Contributed by Sebastian Rittau in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=42012">bpo-42012</a>.)</p></li>

  728. </ul>

  729. </section>

  730. <section id="improved-modules">

  731. <span id="whatsnew311-improved-modules"></span><h2>Improved Modules<a class="headerlink" href="#improved-modules" title="Link to this heading">¶</a></h2>

  732. <section id="asyncio">

  733. <span id="whatsnew311-asyncio"></span><h3>asyncio<a class="headerlink" href="#asyncio" title="Link to this heading">¶</a></h3>

  734. <ul class="simple">

  735. <li><p>Added the <a class="reference internal" href="../library/asyncio-task.html#asyncio.TaskGroup" title="asyncio.TaskGroup"><code class="xref py py-class docutils literal notranslate"><span class="pre">TaskGroup</span></code></a> class,

  736. an <a class="reference internal" href="../reference/datamodel.html#async-context-managers"><span class="std std-ref">asynchronous context manager</span></a>

  737. holding a group of tasks that will wait for all of them upon exit.

  738. For new code this is recommended over using

  739. <a class="reference internal" href="../library/asyncio-task.html#asyncio.create_task" title="asyncio.create_task"><code class="xref py py-func docutils literal notranslate"><span class="pre">create_task()</span></code></a> and <a class="reference internal" href="../library/asyncio-task.html#asyncio.gather" title="asyncio.gather"><code class="xref py py-func docutils literal notranslate"><span class="pre">gather()</span></code></a> directly.

  740. (Contributed by Yury Selivanov and others in <a class="reference external" href="https://github.com/python/cpython/issues/90908">gh-90908</a>.)</p></li>

  741. <li><p>Added <a class="reference internal" href="../library/asyncio-task.html#asyncio.timeout" title="asyncio.timeout"><code class="xref py py-func docutils literal notranslate"><span class="pre">timeout()</span></code></a>, an asynchronous context manager for

  742. setting a timeout on asynchronous operations. For new code this is

  743. recommended over using <a class="reference internal" href="../library/asyncio-task.html#asyncio.wait_for" title="asyncio.wait_for"><code class="xref py py-func docutils literal notranslate"><span class="pre">wait_for()</span></code></a> directly.

  744. (Contributed by Andrew Svetlov in <a class="reference external" href="https://github.com/python/cpython/issues/90927">gh-90927</a>.)</p></li>

  745. <li><p>Added the <a class="reference internal" href="../library/asyncio-runner.html#asyncio.Runner" title="asyncio.Runner"><code class="xref py py-class docutils literal notranslate"><span class="pre">Runner</span></code></a> class, which exposes the machinery

  746. used by <a class="reference internal" href="../library/asyncio-runner.html#asyncio.run" title="asyncio.run"><code class="xref py py-func docutils literal notranslate"><span class="pre">run()</span></code></a>.

  747. (Contributed by Andrew Svetlov in <a class="reference external" href="https://github.com/python/cpython/issues/91218">gh-91218</a>.)</p></li>

  748. <li><p>Added the <a class="reference internal" href="../library/asyncio-sync.html#asyncio.Barrier" title="asyncio.Barrier"><code class="xref py py-class docutils literal notranslate"><span class="pre">Barrier</span></code></a> class to the synchronization

  749. primitives in the asyncio library, and the related

  750. <a class="reference internal" href="../library/asyncio-sync.html#asyncio.BrokenBarrierError" title="asyncio.BrokenBarrierError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">BrokenBarrierError</span></code></a> exception.

  751. (Contributed by Yves Duprat and Andrew Svetlov in <a class="reference external" href="https://github.com/python/cpython/issues/87518">gh-87518</a>.)</p></li>

  752. <li><p>Added keyword argument <em>all_errors</em> to <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.loop.create_connection" title="asyncio.loop.create_connection"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.loop.create_connection()</span></code></a>

  753. so that multiple connection errors can be raised as an <a class="reference internal" href="../library/exceptions.html#ExceptionGroup" title="ExceptionGroup"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ExceptionGroup</span></code></a>.</p></li>

  754. <li><p>Added the <a class="reference internal" href="../library/asyncio-stream.html#asyncio.StreamWriter.start_tls" title="asyncio.StreamWriter.start_tls"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.StreamWriter.start_tls()</span></code></a> method for

  755. upgrading existing stream-based connections to TLS.

  756. (Contributed by Ian Good in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=34975">bpo-34975</a>.)</p></li>

  757. <li><p>Added raw datagram socket functions to the event loop:

  758. <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.loop.sock_sendto" title="asyncio.loop.sock_sendto"><code class="xref py py-meth docutils literal notranslate"><span class="pre">sock_sendto()</span></code></a>,

  759. <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.loop.sock_recvfrom" title="asyncio.loop.sock_recvfrom"><code class="xref py py-meth docutils literal notranslate"><span class="pre">sock_recvfrom()</span></code></a> and

  760. <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.loop.sock_recvfrom_into" title="asyncio.loop.sock_recvfrom_into"><code class="xref py py-meth docutils literal notranslate"><span class="pre">sock_recvfrom_into()</span></code></a>.

  761. These have implementations in <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.SelectorEventLoop" title="asyncio.SelectorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">SelectorEventLoop</span></code></a> and

  762. <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a>.

  763. (Contributed by Alex Grönholm in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46805">bpo-46805</a>.)</p></li>

  764. <li><p>Added <a class="reference internal" href="../library/asyncio-task.html#asyncio.Task.cancelling" title="asyncio.Task.cancelling"><code class="xref py py-meth docutils literal notranslate"><span class="pre">cancelling()</span></code></a> and

  765. <a class="reference internal" href="../library/asyncio-task.html#asyncio.Task.uncancel" title="asyncio.Task.uncancel"><code class="xref py py-meth docutils literal notranslate"><span class="pre">uncancel()</span></code></a> methods to <a class="reference internal" href="../library/asyncio-task.html#asyncio.Task" title="asyncio.Task"><code class="xref py py-class docutils literal notranslate"><span class="pre">Task</span></code></a>.

  766. These are primarily intended for internal use,

  767. notably by <a class="reference internal" href="../library/asyncio-task.html#asyncio.TaskGroup" title="asyncio.TaskGroup"><code class="xref py py-class docutils literal notranslate"><span class="pre">TaskGroup</span></code></a>.</p></li>

  768. </ul>

  769. </section>

  770. <section id="contextlib">

  771. <span id="whatsnew311-contextlib"></span><h3>contextlib<a class="headerlink" href="#contextlib" title="Link to this heading">¶</a></h3>

  772. <ul class="simple">

  773. <li><p>Added non parallel-safe <a class="reference internal" href="../library/contextlib.html#contextlib.chdir" title="contextlib.chdir"><code class="xref py py-func docutils literal notranslate"><span class="pre">chdir()</span></code></a> context manager to change

  774. the current working directory and then restore it on exit. Simple wrapper

  775. around <a class="reference internal" href="../library/os.html#os.chdir" title="os.chdir"><code class="xref py py-func docutils literal notranslate"><span class="pre">chdir()</span></code></a>. (Contributed by Filipe Laíns in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=25625">bpo-25625</a>)</p></li>

  776. </ul>

  777. </section>

  778. <section id="dataclasses">

  779. <span id="whatsnew311-dataclasses"></span><h3>dataclasses<a class="headerlink" href="#dataclasses" title="Link to this heading">¶</a></h3>

  780. <ul class="simple">

  781. <li><p>Change field default mutability check, allowing only defaults which are

  782. <a class="reference internal" href="../glossary.html#term-hashable"><span class="xref std std-term">hashable</span></a> instead of any object which is not an instance of

  783. <a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate"><span class="pre">dict</span></code></a>, <a class="reference internal" href="../library/stdtypes.html#list" title="list"><code class="xref py py-class docutils literal notranslate"><span class="pre">list</span></code></a> or <a class="reference internal" href="../library/stdtypes.html#set" title="set"><code class="xref py py-class docutils literal notranslate"><span class="pre">set</span></code></a>. (Contributed by Eric V. Smith in

  784. <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44674">bpo-44674</a>.)</p></li>

  785. </ul>

  786. </section>

  787. <section id="datetime">

  788. <span id="whatsnew311-datetime"></span><h3>datetime<a class="headerlink" href="#datetime" title="Link to this heading">¶</a></h3>

  789. <ul class="simple">

  790. <li><p>Add <a class="reference internal" href="../library/datetime.html#datetime.UTC" title="datetime.UTC"><code class="xref py py-const docutils literal notranslate"><span class="pre">datetime.UTC</span></code></a>, a convenience alias for

  791. <a class="reference internal" href="../library/datetime.html#datetime.timezone.utc" title="datetime.timezone.utc"><code class="xref py py-attr docutils literal notranslate"><span class="pre">datetime.timezone.utc</span></code></a>. (Contributed by Kabir Kwatra in <a class="reference external" href="https://github.com/python/cpython/issues/91973">gh-91973</a>.)</p></li>

  792. <li><p><a class="reference internal" href="../library/datetime.html#datetime.date.fromisoformat" title="datetime.date.fromisoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.date.fromisoformat()</span></code></a>, <a class="reference internal" href="../library/datetime.html#datetime.time.fromisoformat" title="datetime.time.fromisoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.time.fromisoformat()</span></code></a> and

  793. <a class="reference internal" href="../library/datetime.html#datetime.datetime.fromisoformat" title="datetime.datetime.fromisoformat"><code class="xref py py-meth docutils literal notranslate"><span class="pre">datetime.datetime.fromisoformat()</span></code></a> can now be used to parse most ISO 8601

  794. formats (barring only those that support fractional hours and minutes).

  795. (Contributed by Paul Ganssle in <a class="reference external" href="https://github.com/python/cpython/issues/80010">gh-80010</a>.)</p></li>

  796. </ul>

  797. </section>

  798. <section id="enum">

  799. <span id="whatsnew311-enum"></span><h3>enum<a class="headerlink" href="#enum" title="Link to this heading">¶</a></h3>

  800. <ul class="simple">

  801. <li><p>Renamed <code class="xref py py-class docutils literal notranslate"><span class="pre">EnumMeta</span></code> to <a class="reference internal" href="../library/enum.html#enum.EnumType" title="enum.EnumType"><code class="xref py py-class docutils literal notranslate"><span class="pre">EnumType</span></code></a>

  802. (<code class="xref py py-class docutils literal notranslate"><span class="pre">EnumMeta</span></code> kept as an alias).</p></li>

  803. <li><p>Added <a class="reference internal" href="../library/enum.html#enum.StrEnum" title="enum.StrEnum"><code class="xref py py-class docutils literal notranslate"><span class="pre">StrEnum</span></code></a>,

  804. with members that can be used as (and must be) strings.</p></li>

  805. <li><p>Added <a class="reference internal" href="../library/enum.html#enum.ReprEnum" title="enum.ReprEnum"><code class="xref py py-class docutils literal notranslate"><span class="pre">ReprEnum</span></code></a>,

  806. which only modifies the <a class="reference internal" href="../reference/datamodel.html#object.__repr__" title="object.__repr__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__repr__()</span></code></a> of members

  807. while returning their literal values (rather than names)

  808. for <a class="reference internal" href="../reference/datamodel.html#object.__str__" title="object.__str__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__str__()</span></code></a> and <a class="reference internal" href="../reference/datamodel.html#object.__format__" title="object.__format__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__format__()</span></code></a>

  809. (used by <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-func docutils literal notranslate"><span class="pre">str()</span></code></a>, <a class="reference internal" href="../library/functions.html#format" title="format"><code class="xref py py-func docutils literal notranslate"><span class="pre">format()</span></code></a> and <a class="reference internal" href="../glossary.html#term-f-string"><span class="xref std std-term">f-string</span></a>s).</p></li>

  810. <li><p>Changed <a class="reference internal" href="../library/enum.html#enum.Enum.__format__" title="enum.Enum.__format__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Enum.__format__()</span></code></a> (the default for

  811. <a class="reference internal" href="../library/functions.html#format" title="format"><code class="xref py py-func docutils literal notranslate"><span class="pre">format()</span></code></a>, <a class="reference internal" href="../library/stdtypes.html#str.format" title="str.format"><code class="xref py py-meth docutils literal notranslate"><span class="pre">str.format()</span></code></a> and <a class="reference internal" href="../glossary.html#term-f-string"><span class="xref std std-term">f-string</span></a>s) to always produce

  812. the same result as <a class="reference internal" href="../library/enum.html#enum.Enum.__str__" title="enum.Enum.__str__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Enum.__str__()</span></code></a>:  for enums inheriting from

  813. <a class="reference internal" href="../library/enum.html#enum.ReprEnum" title="enum.ReprEnum"><code class="xref py py-class docutils literal notranslate"><span class="pre">ReprEnum</span></code></a> it will be the member’s value; for all other enums

  814. it will be the enum and member name (e.g. <code class="docutils literal notranslate"><span class="pre">Color.RED</span></code>).</p></li>

  815. <li><p>Added a new <em>boundary</em> class parameter to <a class="reference internal" href="../library/enum.html#enum.Flag" title="enum.Flag"><code class="xref py py-class docutils literal notranslate"><span class="pre">Flag</span></code></a> enums

  816. and the <a class="reference internal" href="../library/enum.html#enum.FlagBoundary" title="enum.FlagBoundary"><code class="xref py py-class docutils literal notranslate"><span class="pre">FlagBoundary</span></code></a> enum with its options,

  817. to control how to handle out-of-range flag values.</p></li>

  818. <li><p>Added the <a class="reference internal" href="../library/enum.html#enum.verify" title="enum.verify"><code class="xref py py-func docutils literal notranslate"><span class="pre">verify()</span></code></a> enum decorator

  819. and the <a class="reference internal" href="../library/enum.html#enum.EnumCheck" title="enum.EnumCheck"><code class="xref py py-class docutils literal notranslate"><span class="pre">EnumCheck</span></code></a> enum with its options,

  820. to check enum classes against several specific constraints.</p></li>

  821. <li><p>Added the <a class="reference internal" href="../library/enum.html#enum.member" title="enum.member"><code class="xref py py-func docutils literal notranslate"><span class="pre">member()</span></code></a> and <a class="reference internal" href="../library/enum.html#enum.nonmember" title="enum.nonmember"><code class="xref py py-func docutils literal notranslate"><span class="pre">nonmember()</span></code></a> decorators,

  822. to ensure the decorated object is/is not converted to an enum member.</p></li>

  823. <li><p>Added the <a class="reference internal" href="../library/enum.html#enum.property" title="enum.property"><code class="xref py py-func docutils literal notranslate"><span class="pre">property()</span></code></a> decorator,

  824. which works like <a class="reference internal" href="../library/functions.html#property" title="property"><code class="xref py py-func docutils literal notranslate"><span class="pre">property()</span></code></a> except for enums.

  825. Use this instead of <a class="reference internal" href="../library/types.html#types.DynamicClassAttribute" title="types.DynamicClassAttribute"><code class="xref py py-func docutils literal notranslate"><span class="pre">types.DynamicClassAttribute()</span></code></a>.</p></li>

  826. <li><p>Added the <a class="reference internal" href="../library/enum.html#enum.global_enum" title="enum.global_enum"><code class="xref py py-func docutils literal notranslate"><span class="pre">global_enum()</span></code></a> enum decorator,

  827. which adjusts <a class="reference internal" href="../reference/datamodel.html#object.__repr__" title="object.__repr__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__repr__()</span></code></a> and <a class="reference internal" href="../reference/datamodel.html#object.__str__" title="object.__str__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__str__()</span></code></a>

  828. to show values as members of their module rather than the enum class.

  829. For example, <code class="docutils literal notranslate"><span class="pre">'re.ASCII'</span></code> for the <a class="reference internal" href="../library/re.html#re.ASCII" title="re.ASCII"><code class="xref py py-const docutils literal notranslate"><span class="pre">ASCII</span></code></a> member

  830. of <a class="reference internal" href="../library/re.html#re.RegexFlag" title="re.RegexFlag"><code class="xref py py-class docutils literal notranslate"><span class="pre">re.RegexFlag</span></code></a> rather than <code class="docutils literal notranslate"><span class="pre">'RegexFlag.ASCII'</span></code>.</p></li>

  831. <li><p>Enhanced <a class="reference internal" href="../library/enum.html#enum.Flag" title="enum.Flag"><code class="xref py py-class docutils literal notranslate"><span class="pre">Flag</span></code></a> to support

  832. <a class="reference internal" href="../library/functions.html#len" title="len"><code class="xref py py-func docutils literal notranslate"><span class="pre">len()</span></code></a>, iteration and <a class="reference internal" href="../reference/expressions.html#in"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">in</span></code></a>/<a class="reference internal" href="../reference/expressions.html#not-in"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">not</span> <span class="pre">in</span></code></a> on its members.

  833. For example, the following now works:

  834. <code class="docutils literal notranslate"><span class="pre">len(AFlag(3))</span> <span class="pre">==</span> <span class="pre">2</span> <span class="pre">and</span> <span class="pre">list(AFlag(3))</span> <span class="pre">==</span> <span class="pre">(AFlag.ONE,</span> <span class="pre">AFlag.TWO)</span></code></p></li>

  835. <li><p>Changed <a class="reference internal" href="../library/enum.html#enum.Enum" title="enum.Enum"><code class="xref py py-class docutils literal notranslate"><span class="pre">Enum</span></code></a> and <a class="reference internal" href="../library/enum.html#enum.Flag" title="enum.Flag"><code class="xref py py-class docutils literal notranslate"><span class="pre">Flag</span></code></a>

  836. so that members are now defined

  837. before <a class="reference internal" href="../reference/datamodel.html#object.__init_subclass__" title="object.__init_subclass__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__init_subclass__()</span></code></a> is called;

  838. <a class="reference internal" href="../library/functions.html#dir" title="dir"><code class="xref py py-func docutils literal notranslate"><span class="pre">dir()</span></code></a> now includes methods, etc., from mixed-in data types.</p></li>

  839. <li><p>Changed <a class="reference internal" href="../library/enum.html#enum.Flag" title="enum.Flag"><code class="xref py py-class docutils literal notranslate"><span class="pre">Flag</span></code></a>

  840. to only consider primary values (power of two) canonical

  841. while composite values (<code class="docutils literal notranslate"><span class="pre">3</span></code>, <code class="docutils literal notranslate"><span class="pre">6</span></code>, <code class="docutils literal notranslate"><span class="pre">10</span></code>, etc.) are considered aliases;

  842. inverted flags are coerced to their positive equivalent.</p></li>

  843. </ul>

  844. </section>

  845. <section id="fcntl">

  846. <span id="whatsnew311-fcntl"></span><h3>fcntl<a class="headerlink" href="#fcntl" title="Link to this heading">¶</a></h3>

  847. <ul class="simple">

  848. <li><p>On FreeBSD, the <code class="xref py py-data docutils literal notranslate"><span class="pre">F_DUP2FD</span></code> and <code class="xref py py-data docutils literal notranslate"><span class="pre">F_DUP2FD_CLOEXEC</span></code> flags respectively

  849. are supported, the former equals to <code class="docutils literal notranslate"><span class="pre">dup2</span></code> usage while the latter set

  850. the <code class="docutils literal notranslate"><span class="pre">FD_CLOEXEC</span></code> flag in addition.</p></li>

  851. </ul>

  852. </section>

  853. <section id="fractions">

  854. <span id="whatsnew311-fractions"></span><h3>fractions<a class="headerlink" href="#fractions" title="Link to this heading">¶</a></h3>

  855. <ul class="simple">

  856. <li><p>Support <span class="target" id="index-26"></span><a class="pep reference external" href="https://peps.python.org/pep-0515/"><strong>PEP 515</strong></a>-style initialization of <a class="reference internal" href="../library/fractions.html#fractions.Fraction" title="fractions.Fraction"><code class="xref py py-class docutils literal notranslate"><span class="pre">Fraction</span></code></a> from

  857. string.  (Contributed by Sergey B Kirpichev in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44258">bpo-44258</a>.)</p></li>

  858. <li><p><a class="reference internal" href="../library/fractions.html#fractions.Fraction" title="fractions.Fraction"><code class="xref py py-class docutils literal notranslate"><span class="pre">Fraction</span></code></a> now implements an <code class="docutils literal notranslate"><span class="pre">__int__</span></code> method, so

  859. that an <code class="docutils literal notranslate"><span class="pre">isinstance(some_fraction,</span> <span class="pre">typing.SupportsInt)</span></code> check passes.

  860. (Contributed by Mark Dickinson in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44547">bpo-44547</a>.)</p></li>

  861. </ul>

  862. </section>

  863. <section id="functools">

  864. <span id="whatsnew311-functools"></span><h3>functools<a class="headerlink" href="#functools" title="Link to this heading">¶</a></h3>

  865. <ul>

  866. <li><p><a class="reference internal" href="../library/functools.html#functools.singledispatch" title="functools.singledispatch"><code class="xref py py-func docutils literal notranslate"><span class="pre">functools.singledispatch()</span></code></a> now supports <a class="reference internal" href="../library/types.html#types.UnionType" title="types.UnionType"><code class="xref py py-data docutils literal notranslate"><span class="pre">types.UnionType</span></code></a>

  867. and <a class="reference internal" href="../library/typing.html#typing.Union" title="typing.Union"><code class="xref py py-data docutils literal notranslate"><span class="pre">typing.Union</span></code></a> as annotations to the dispatch argument.:</p>

  868. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="kn">from</span> <span class="nn">functools</span> <span class="kn">import</span> <span class="n">singledispatch</span>

  869. <span class="gp">&gt;&gt;&gt; </span><span class="nd">@singledispatch</span>

  870. <span class="gp">... </span><span class="k">def</span> <span class="nf">fun</span><span class="p">(</span><span class="n">arg</span><span class="p">,</span> <span class="n">verbose</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span>

  871. <span class="gp">... </span>    <span class="k">if</span> <span class="n">verbose</span><span class="p">:</span>

  872. <span class="gp">... </span>        <span class="nb">print</span><span class="p">(</span><span class="s2">&quot;Let me just say,&quot;</span><span class="p">,</span> <span class="n">end</span><span class="o">=</span><span class="s2">&quot; &quot;</span><span class="p">)</span>

  873. <span class="gp">... </span>    <span class="nb">print</span><span class="p">(</span><span class="n">arg</span><span class="p">)</span>

  874. <span class="gp">...</span>

  875. <span class="gp">&gt;&gt;&gt; </span><span class="nd">@fun</span><span class="o">.</span><span class="n">register</span>

  876. <span class="gp">... </span><span class="k">def</span> <span class="nf">_</span><span class="p">(</span><span class="n">arg</span><span class="p">:</span> <span class="nb">int</span> <span class="o">|</span> <span class="nb">float</span><span class="p">,</span> <span class="n">verbose</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span>

  877. <span class="gp">... </span>    <span class="k">if</span> <span class="n">verbose</span><span class="p">:</span>

  878. <span class="gp">... </span>        <span class="nb">print</span><span class="p">(</span><span class="s2">&quot;Strength in numbers, eh?&quot;</span><span class="p">,</span> <span class="n">end</span><span class="o">=</span><span class="s2">&quot; &quot;</span><span class="p">)</span>

  879. <span class="gp">... </span>    <span class="nb">print</span><span class="p">(</span><span class="n">arg</span><span class="p">)</span>

  880. <span class="gp">...</span>

  881. <span class="gp">&gt;&gt;&gt; </span><span class="kn">from</span> <span class="nn">typing</span> <span class="kn">import</span> <span class="n">Union</span>

  882. <span class="gp">&gt;&gt;&gt; </span><span class="nd">@fun</span><span class="o">.</span><span class="n">register</span>

  883. <span class="gp">... </span><span class="k">def</span> <span class="nf">_</span><span class="p">(</span><span class="n">arg</span><span class="p">:</span> <span class="n">Union</span><span class="p">[</span><span class="nb">list</span><span class="p">,</span> <span class="nb">set</span><span class="p">],</span> <span class="n">verbose</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span>

  884. <span class="gp">... </span>    <span class="k">if</span> <span class="n">verbose</span><span class="p">:</span>

  885. <span class="gp">... </span>        <span class="nb">print</span><span class="p">(</span><span class="s2">&quot;Enumerate this:&quot;</span><span class="p">)</span>

  886. <span class="gp">... </span>    <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">elem</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">arg</span><span class="p">):</span>

  887. <span class="gp">... </span>        <span class="nb">print</span><span class="p">(</span><span class="n">i</span><span class="p">,</span> <span class="n">elem</span><span class="p">)</span>

  888. <span class="gp">...</span>

  889. </pre></div>

  890. </div>

  891. <p>(Contributed by Yurii Karabas in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46014">bpo-46014</a>.)</p>

  892. </li>

  893. </ul>

  894. </section>

  895. <section id="hashlib">

  896. <span id="whatsnew311-hashlib"></span><h3>hashlib<a class="headerlink" href="#hashlib" title="Link to this heading">¶</a></h3>

  897. <ul class="simple">

  898. <li><p><a class="reference internal" href="../library/hashlib.html#hashlib.blake2b" title="hashlib.blake2b"><code class="xref py py-func docutils literal notranslate"><span class="pre">hashlib.blake2b()</span></code></a> and <a class="reference internal" href="../library/hashlib.html#hashlib.blake2s" title="hashlib.blake2s"><code class="xref py py-func docutils literal notranslate"><span class="pre">hashlib.blake2s()</span></code></a> now prefer <a class="reference external" href="https://www.blake2.net/">libb2</a>

  899. over Python’s vendored copy.

  900. (Contributed by Christian Heimes in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47095">bpo-47095</a>.)</p></li>

  901. <li><p>The internal <code class="docutils literal notranslate"><span class="pre">_sha3</span></code> module with SHA3 and SHAKE algorithms now uses

  902. <em>tiny_sha3</em> instead of the <em>Keccak Code Package</em> to reduce code and binary

  903. size. The <a class="reference internal" href="../library/hashlib.html#module-hashlib" title="hashlib: Secure hash and message digest algorithms."><code class="xref py py-mod docutils literal notranslate"><span class="pre">hashlib</span></code></a> module prefers optimized SHA3 and SHAKE

  904. implementations from OpenSSL. The change affects only installations without

  905. OpenSSL support.

  906. (Contributed by Christian Heimes in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47098">bpo-47098</a>.)</p></li>

  907. <li><p>Add <a class="reference internal" href="../library/hashlib.html#hashlib.file_digest" title="hashlib.file_digest"><code class="xref py py-func docutils literal notranslate"><span class="pre">hashlib.file_digest()</span></code></a>, a helper function for efficient hashing

  908. of files or file-like objects.

  909. (Contributed by Christian Heimes in <a class="reference external" href="https://github.com/python/cpython/issues/89313">gh-89313</a>.)</p></li>

  910. </ul>

  911. </section>

  912. <section id="whatsnew311-idle">

  913. <span id="idle-and-idlelib"></span><h3>IDLE and idlelib<a class="headerlink" href="#whatsnew311-idle" title="Link to this heading">¶</a></h3>

  914. <ul class="simple">

  915. <li><p>Apply syntax highlighting to <code class="docutils literal notranslate"><span class="pre">.pyi</span></code> files. (Contributed by Alex

  916. Waygood and Terry Jan Reedy in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45447">bpo-45447</a>.)</p></li>

  917. <li><p>Include prompts when saving Shell with inputs and outputs.

  918. (Contributed by Terry Jan Reedy in <a class="reference external" href="https://github.com/python/cpython/issues/95191">gh-95191</a>.)</p></li>

  919. </ul>

  920. </section>

  921. <section id="inspect">

  922. <span id="whatsnew311-inspect"></span><h3>inspect<a class="headerlink" href="#inspect" title="Link to this heading">¶</a></h3>

  923. <ul>

  924. <li><p>Add <a class="reference internal" href="../library/inspect.html#inspect.getmembers_static" title="inspect.getmembers_static"><code class="xref py py-func docutils literal notranslate"><span class="pre">getmembers_static()</span></code></a> to return all members without

  925. triggering dynamic lookup via the descriptor protocol. (Contributed by

  926. Weipeng Hong in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=30533">bpo-30533</a>.)</p></li>

  927. <li><p>Add <a class="reference internal" href="../library/inspect.html#inspect.ismethodwrapper" title="inspect.ismethodwrapper"><code class="xref py py-func docutils literal notranslate"><span class="pre">ismethodwrapper()</span></code></a>

  928. for checking if the type of an object is a <a class="reference internal" href="../library/types.html#types.MethodWrapperType" title="types.MethodWrapperType"><code class="xref py py-class docutils literal notranslate"><span class="pre">MethodWrapperType</span></code></a>.

  929. (Contributed by Hakan Çelik in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=29418">bpo-29418</a>.)</p></li>

  930. <li><p>Change the frame-related functions in the <a class="reference internal" href="../library/inspect.html#module-inspect" title="inspect: Extract information and source code from live objects."><code class="xref py py-mod docutils literal notranslate"><span class="pre">inspect</span></code></a> module to return new

  931. <a class="reference internal" href="../library/inspect.html#inspect.FrameInfo" title="inspect.FrameInfo"><code class="xref py py-class docutils literal notranslate"><span class="pre">FrameInfo</span></code></a> and <a class="reference internal" href="../library/inspect.html#inspect.Traceback" title="inspect.Traceback"><code class="xref py py-class docutils literal notranslate"><span class="pre">Traceback</span></code></a> class instances

  932. (backwards compatible with the previous <a class="reference internal" href="../glossary.html#term-named-tuple"><span class="xref std std-term">named tuple</span></a>-like interfaces)

  933. that includes the extended <span class="target" id="index-27"></span><a class="pep reference external" href="https://peps.python.org/pep-0657/"><strong>PEP 657</strong></a> position information (end

  934. line number, column and end column). The affected functions are:</p>

  935. <ul class="simple">

  936. <li><p><a class="reference internal" href="../library/inspect.html#inspect.getframeinfo" title="inspect.getframeinfo"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.getframeinfo()</span></code></a></p></li>

  937. <li><p><a class="reference internal" href="../library/inspect.html#inspect.getouterframes" title="inspect.getouterframes"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.getouterframes()</span></code></a></p></li>

  938. <li><p><a class="reference internal" href="../library/inspect.html#inspect.getinnerframes" title="inspect.getinnerframes"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.getinnerframes()</span></code></a>,</p></li>

  939. <li><p><a class="reference internal" href="../library/inspect.html#inspect.stack" title="inspect.stack"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.stack()</span></code></a></p></li>

  940. <li><p><a class="reference internal" href="../library/inspect.html#inspect.trace" title="inspect.trace"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.trace()</span></code></a></p></li>

  941. </ul>

  942. <p>(Contributed by Pablo Galindo in <a class="reference external" href="https://github.com/python/cpython/issues/88116">gh-88116</a>.)</p>

  943. </li>

  944. </ul>

  945. </section>

  946. <section id="locale">

  947. <span id="whatsnew311-locale"></span><h3>locale<a class="headerlink" href="#locale" title="Link to this heading">¶</a></h3>

  948. <ul class="simple">

  949. <li><p>Add <a class="reference internal" href="../library/locale.html#locale.getencoding" title="locale.getencoding"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.getencoding()</span></code></a> to get the current locale encoding. It is similar to

  950. <code class="docutils literal notranslate"><span class="pre">locale.getpreferredencoding(False)</span></code> but ignores the

  951. <a class="reference internal" href="../library/os.html#utf8-mode"><span class="std std-ref">Python UTF-8 Mode</span></a>.</p></li>

  952. </ul>

  953. </section>

  954. <section id="logging">

  955. <span id="whatsnew311-logging"></span><h3>logging<a class="headerlink" href="#logging" title="Link to this heading">¶</a></h3>

  956. <ul class="simple">

  957. <li><p>Added <a class="reference internal" href="../library/logging.html#logging.getLevelNamesMapping" title="logging.getLevelNamesMapping"><code class="xref py py-func docutils literal notranslate"><span class="pre">getLevelNamesMapping()</span></code></a>

  958. to return a mapping from logging level names (e.g. <code class="docutils literal notranslate"><span class="pre">'CRITICAL'</span></code>)

  959. to the values of their corresponding <a class="reference internal" href="../library/logging.html#levels"><span class="std std-ref">Logging Levels</span></a> (e.g. <code class="docutils literal notranslate"><span class="pre">50</span></code>, by default).

  960. (Contributed by Andrei Kulakovin in <a class="reference external" href="https://github.com/python/cpython/issues/88024">gh-88024</a>.)</p></li>

  961. <li><p>Added a <a class="reference internal" href="../library/logging.handlers.html#logging.handlers.SysLogHandler.createSocket" title="logging.handlers.SysLogHandler.createSocket"><code class="xref py py-meth docutils literal notranslate"><span class="pre">createSocket()</span></code></a> method

  962. to <a class="reference internal" href="../library/logging.handlers.html#logging.handlers.SysLogHandler" title="logging.handlers.SysLogHandler"><code class="xref py py-class docutils literal notranslate"><span class="pre">SysLogHandler</span></code></a>, to match

  963. <a class="reference internal" href="../library/logging.handlers.html#logging.handlers.SocketHandler.createSocket" title="logging.handlers.SocketHandler.createSocket"><code class="xref py py-meth docutils literal notranslate"><span class="pre">SocketHandler.createSocket()</span></code></a>.

  964. It is called automatically during handler initialization

  965. and when emitting an event, if there is no active socket.

  966. (Contributed by Kirill Pinchuk in <a class="reference external" href="https://github.com/python/cpython/issues/88457">gh-88457</a>.)</p></li>

  967. </ul>

  968. </section>

  969. <section id="math">

  970. <span id="whatsnew311-math"></span><h3>math<a class="headerlink" href="#math" title="Link to this heading">¶</a></h3>

  971. <ul class="simple">

  972. <li><p>Add <a class="reference internal" href="../library/math.html#math.exp2" title="math.exp2"><code class="xref py py-func docutils literal notranslate"><span class="pre">math.exp2()</span></code></a>: return 2 raised to the power of x.

  973. (Contributed by Gideon Mitchell in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45917">bpo-45917</a>.)</p></li>

  974. <li><p>Add <a class="reference internal" href="../library/math.html#math.cbrt" title="math.cbrt"><code class="xref py py-func docutils literal notranslate"><span class="pre">math.cbrt()</span></code></a>: return the cube root of x.

  975. (Contributed by Ajith Ramachandran in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44357">bpo-44357</a>.)</p></li>

  976. <li><p>The behaviour of two <a class="reference internal" href="../library/math.html#math.pow" title="math.pow"><code class="xref py py-func docutils literal notranslate"><span class="pre">math.pow()</span></code></a> corner cases was changed, for

  977. consistency with the IEEE 754 specification. The operations

  978. <code class="docutils literal notranslate"><span class="pre">math.pow(0.0,</span> <span class="pre">-math.inf)</span></code> and <code class="docutils literal notranslate"><span class="pre">math.pow(-0.0,</span> <span class="pre">-math.inf)</span></code> now return

  979. <code class="docutils literal notranslate"><span class="pre">inf</span></code>. Previously they raised <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a>. (Contributed by Mark

  980. Dickinson in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44339">bpo-44339</a>.)</p></li>

  981. <li><p>The <a class="reference internal" href="../library/math.html#math.nan" title="math.nan"><code class="xref py py-data docutils literal notranslate"><span class="pre">math.nan</span></code></a> value is now always available.

  982. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46917">bpo-46917</a>.)</p></li>

  983. </ul>

  984. </section>

  985. <section id="operator">

  986. <span id="whatsnew311-operator"></span><h3>operator<a class="headerlink" href="#operator" title="Link to this heading">¶</a></h3>

  987. <ul class="simple">

  988. <li><p>A new function <code class="docutils literal notranslate"><span class="pre">operator.call</span></code> has been added, such that

  989. <code class="docutils literal notranslate"><span class="pre">operator.call(obj,</span> <span class="pre">*args,</span> <span class="pre">**kwargs)</span> <span class="pre">==</span> <span class="pre">obj(*args,</span> <span class="pre">**kwargs)</span></code>.

  990. (Contributed by Antony Lee in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44019">bpo-44019</a>.)</p></li>

  991. </ul>

  992. </section>

  993. <section id="os">

  994. <span id="whatsnew311-os"></span><h3>os<a class="headerlink" href="#os" title="Link to this heading">¶</a></h3>

  995. <ul class="simple">

  996. <li><p>On Windows, <a class="reference internal" href="../library/os.html#os.urandom" title="os.urandom"><code class="xref py py-func docutils literal notranslate"><span class="pre">os.urandom()</span></code></a> now uses <code class="docutils literal notranslate"><span class="pre">BCryptGenRandom()</span></code>,

  997. instead of <code class="docutils literal notranslate"><span class="pre">CryptGenRandom()</span></code> which is deprecated.

  998. (Contributed by Donghee Na in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44611">bpo-44611</a>.)</p></li>

  999. </ul>

  1000. </section>

  1001. <section id="pathlib">

  1002. <span id="whatsnew311-pathlib"></span><h3>pathlib<a class="headerlink" href="#pathlib" title="Link to this heading">¶</a></h3>

  1003. <ul class="simple">

  1004. <li><p><a class="reference internal" href="../library/pathlib.html#pathlib.Path.glob" title="pathlib.Path.glob"><code class="xref py py-meth docutils literal notranslate"><span class="pre">glob()</span></code></a> and <a class="reference internal" href="../library/pathlib.html#pathlib.Path.rglob" title="pathlib.Path.rglob"><code class="xref py py-meth docutils literal notranslate"><span class="pre">rglob()</span></code></a> return only

  1005. directories if <em>pattern</em> ends with a pathname components separator:

  1006. <a class="reference internal" href="../library/os.html#os.sep" title="os.sep"><code class="xref py py-data docutils literal notranslate"><span class="pre">sep</span></code></a> or <a class="reference internal" href="../library/os.html#os.altsep" title="os.altsep"><code class="xref py py-data docutils literal notranslate"><span class="pre">altsep</span></code></a>.

  1007. (Contributed by Eisuke Kawasima in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=22276">bpo-22276</a> and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=33392">bpo-33392</a>.)</p></li>

  1008. </ul>

  1009. </section>

  1010. <section id="re">

  1011. <span id="whatsnew311-re"></span><h3>re<a class="headerlink" href="#re" title="Link to this heading">¶</a></h3>

  1012. <ul class="simple">

  1013. <li><p>Atomic grouping (<code class="docutils literal notranslate"><span class="pre">(?&gt;...)</span></code>) and possessive quantifiers (<code class="docutils literal notranslate"><span class="pre">*+</span></code>, <code class="docutils literal notranslate"><span class="pre">++</span></code>,

  1014. <code class="docutils literal notranslate"><span class="pre">?+</span></code>, <code class="docutils literal notranslate"><span class="pre">{m,n}+</span></code>) are now supported in regular expressions.

  1015. (Contributed by Jeffrey C. Jacobs and Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=433030">bpo-433030</a>.)</p></li>

  1016. </ul>

  1017. </section>

  1018. <section id="shutil">

  1019. <span id="whatsnew311-shutil"></span><h3>shutil<a class="headerlink" href="#shutil" title="Link to this heading">¶</a></h3>

  1020. <ul class="simple">

  1021. <li><p>Add optional parameter <em>dir_fd</em> in <a class="reference internal" href="../library/shutil.html#shutil.rmtree" title="shutil.rmtree"><code class="xref py py-func docutils literal notranslate"><span class="pre">shutil.rmtree()</span></code></a>.

  1022. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46245">bpo-46245</a>.)</p></li>

  1023. </ul>

  1024. </section>

  1025. <section id="socket">

  1026. <span id="whatsnew311-socket"></span><h3>socket<a class="headerlink" href="#socket" title="Link to this heading">¶</a></h3>

  1027. <ul class="simple">

  1028. <li><p>Add CAN Socket support for NetBSD.

  1029. (Contributed by Thomas Klausner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=30512">bpo-30512</a>.)</p></li>

  1030. <li><p><a class="reference internal" href="../library/socket.html#socket.create_connection" title="socket.create_connection"><code class="xref py py-meth docutils literal notranslate"><span class="pre">create_connection()</span></code></a> has an option to raise, in case of

  1031. failure to connect, an <a class="reference internal" href="../library/exceptions.html#ExceptionGroup" title="ExceptionGroup"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ExceptionGroup</span></code></a> containing all errors

  1032. instead of only raising the last error.

  1033. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=29980">bpo-29980</a>.)</p></li>

  1034. </ul>

  1035. </section>

  1036. <section id="sqlite3">

  1037. <span id="whatsnew311-sqlite3"></span><h3>sqlite3<a class="headerlink" href="#sqlite3" title="Link to this heading">¶</a></h3>

  1038. <ul class="simple">

  1039. <li><p>You can now disable the authorizer by passing <a class="reference internal" href="../library/constants.html#None" title="None"><code class="xref py py-const docutils literal notranslate"><span class="pre">None</span></code></a> to

  1040. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.set_authorizer" title="sqlite3.Connection.set_authorizer"><code class="xref py py-meth docutils literal notranslate"><span class="pre">set_authorizer()</span></code></a>.

  1041. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44491">bpo-44491</a>.)</p></li>

  1042. <li><p>Collation name <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.create_collation" title="sqlite3.Connection.create_collation"><code class="xref py py-meth docutils literal notranslate"><span class="pre">create_collation()</span></code></a> can now

  1043. contain any Unicode character.  Collation names with invalid characters

  1044. now raise <a class="reference internal" href="../library/exceptions.html#UnicodeEncodeError" title="UnicodeEncodeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">UnicodeEncodeError</span></code></a> instead of <a class="reference internal" href="../library/sqlite3.html#sqlite3.ProgrammingError" title="sqlite3.ProgrammingError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">sqlite3.ProgrammingError</span></code></a>.

  1045. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44688">bpo-44688</a>.)</p></li>

  1046. <li><p><a class="reference internal" href="../library/sqlite3.html#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate"><span class="pre">sqlite3</span></code></a> exceptions now include the SQLite extended error code as

  1047. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Error.sqlite_errorcode" title="sqlite3.Error.sqlite_errorcode"><code class="xref py py-attr docutils literal notranslate"><span class="pre">sqlite_errorcode</span></code></a> and the SQLite error name as

  1048. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Error.sqlite_errorname" title="sqlite3.Error.sqlite_errorname"><code class="xref py py-attr docutils literal notranslate"><span class="pre">sqlite_errorname</span></code></a>.

  1049. (Contributed by Aviv Palivoda, Daniel Shahaf, and Erlend E. Aasland in

  1050. <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=16379">bpo-16379</a> and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=24139">bpo-24139</a>.)</p></li>

  1051. <li><p>Add <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.setlimit" title="sqlite3.Connection.setlimit"><code class="xref py py-meth docutils literal notranslate"><span class="pre">setlimit()</span></code></a> and

  1052. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.getlimit" title="sqlite3.Connection.getlimit"><code class="xref py py-meth docutils literal notranslate"><span class="pre">getlimit()</span></code></a> to <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection" title="sqlite3.Connection"><code class="xref py py-class docutils literal notranslate"><span class="pre">sqlite3.Connection</span></code></a> for

  1053. setting and getting SQLite limits by connection basis.

  1054. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45243">bpo-45243</a>.)</p></li>

  1055. <li><p><a class="reference internal" href="../library/sqlite3.html#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate"><span class="pre">sqlite3</span></code></a> now sets <a class="reference internal" href="../library/sqlite3.html#sqlite3.threadsafety" title="sqlite3.threadsafety"><code class="xref py py-attr docutils literal notranslate"><span class="pre">sqlite3.threadsafety</span></code></a> based on the default

  1056. threading mode the underlying SQLite library has been compiled with.

  1057. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45613">bpo-45613</a>.)</p></li>

  1058. <li><p><a class="reference internal" href="../library/sqlite3.html#module-sqlite3" title="sqlite3: A DB-API 2.0 implementation using SQLite 3.x."><code class="xref py py-mod docutils literal notranslate"><span class="pre">sqlite3</span></code></a> C callbacks now use unraisable exceptions if callback

  1059. tracebacks are enabled. Users can now register an

  1060. <a class="reference internal" href="../library/sys.html#sys.unraisablehook" title="sys.unraisablehook"><code class="xref py py-func docutils literal notranslate"><span class="pre">unraisable</span> <span class="pre">hook</span> <span class="pre">handler</span></code></a> to improve their debug

  1061. experience.

  1062. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45828">bpo-45828</a>.)</p></li>

  1063. <li><p>Fetch across rollback no longer raises <a class="reference internal" href="../library/sqlite3.html#sqlite3.InterfaceError" title="sqlite3.InterfaceError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">InterfaceError</span></code></a>.

  1064. Instead we leave it to the SQLite library to handle these cases.

  1065. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44092">bpo-44092</a>.)</p></li>

  1066. <li><p>Add <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.serialize" title="sqlite3.Connection.serialize"><code class="xref py py-meth docutils literal notranslate"><span class="pre">serialize()</span></code></a> and

  1067. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.deserialize" title="sqlite3.Connection.deserialize"><code class="xref py py-meth docutils literal notranslate"><span class="pre">deserialize()</span></code></a> to <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection" title="sqlite3.Connection"><code class="xref py py-class docutils literal notranslate"><span class="pre">sqlite3.Connection</span></code></a> for

  1068. serializing and deserializing databases.

  1069. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=41930">bpo-41930</a>.)</p></li>

  1070. <li><p>Add <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.create_window_function" title="sqlite3.Connection.create_window_function"><code class="xref py py-meth docutils literal notranslate"><span class="pre">create_window_function()</span></code></a> to

  1071. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection" title="sqlite3.Connection"><code class="xref py py-class docutils literal notranslate"><span class="pre">sqlite3.Connection</span></code></a> for creating aggregate window functions.

  1072. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=34916">bpo-34916</a>.)</p></li>

  1073. <li><p>Add <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection.blobopen" title="sqlite3.Connection.blobopen"><code class="xref py py-meth docutils literal notranslate"><span class="pre">blobopen()</span></code></a> to <a class="reference internal" href="../library/sqlite3.html#sqlite3.Connection" title="sqlite3.Connection"><code class="xref py py-class docutils literal notranslate"><span class="pre">sqlite3.Connection</span></code></a>.

  1074. <a class="reference internal" href="../library/sqlite3.html#sqlite3.Blob" title="sqlite3.Blob"><code class="xref py py-class docutils literal notranslate"><span class="pre">sqlite3.Blob</span></code></a> allows incremental I/O operations on blobs.

  1075. (Contributed by Aviv Palivoda and Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=24905">bpo-24905</a>.)</p></li>

  1076. </ul>

  1077. </section>

  1078. <section id="string">

  1079. <span id="whatsnew311-string"></span><h3>string<a class="headerlink" href="#string" title="Link to this heading">¶</a></h3>

  1080. <ul class="simple">

  1081. <li><p>Add <a class="reference internal" href="../library/string.html#string.Template.get_identifiers" title="string.Template.get_identifiers"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get_identifiers()</span></code></a>

  1082. and <a class="reference internal" href="../library/string.html#string.Template.is_valid" title="string.Template.is_valid"><code class="xref py py-meth docutils literal notranslate"><span class="pre">is_valid()</span></code></a> to <a class="reference internal" href="../library/string.html#string.Template" title="string.Template"><code class="xref py py-class docutils literal notranslate"><span class="pre">string.Template</span></code></a>,

  1083. which respectively return all valid placeholders,

  1084. and whether any invalid placeholders are present.

  1085. (Contributed by Ben Kehoe in <a class="reference external" href="https://github.com/python/cpython/issues/90465">gh-90465</a>.)</p></li>

  1086. </ul>

  1087. </section>

  1088. <section id="sys">

  1089. <span id="whatsnew311-sys"></span><h3>sys<a class="headerlink" href="#sys" title="Link to this heading">¶</a></h3>

  1090. <ul class="simple">

  1091. <li><p><a class="reference internal" href="../library/sys.html#sys.exc_info" title="sys.exc_info"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exc_info()</span></code></a> now derives the <code class="docutils literal notranslate"><span class="pre">type</span></code> and <code class="docutils literal notranslate"><span class="pre">traceback</span></code> fields

  1092. from the <code class="docutils literal notranslate"><span class="pre">value</span></code> (the exception instance), so when an exception is

  1093. modified while it is being handled, the changes are reflected in

  1094. the results of subsequent calls to <code class="xref py py-func docutils literal notranslate"><span class="pre">exc_info()</span></code>.

  1095. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45711">bpo-45711</a>.)</p></li>

  1096. <li><p>Add <a class="reference internal" href="../library/sys.html#sys.exception" title="sys.exception"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exception()</span></code></a> which returns the active exception instance

  1097. (equivalent to <code class="docutils literal notranslate"><span class="pre">sys.exc_info()[1]</span></code>).

  1098. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46328">bpo-46328</a>.)</p></li>

  1099. <li><p>Add the <a class="reference internal" href="../library/sys.html#sys.flags" title="sys.flags"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.flags.safe_path</span></code></a> flag.

  1100. (Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/57684">gh-57684</a>.)</p></li>

  1101. </ul>

  1102. </section>

  1103. <section id="sysconfig">

  1104. <span id="whatsnew311-sysconfig"></span><h3>sysconfig<a class="headerlink" href="#sysconfig" title="Link to this heading">¶</a></h3>

  1105. <ul class="simple">

  1106. <li><p>Three new <a class="reference internal" href="../library/sysconfig.html#installation-paths"><span class="std std-ref">installation schemes</span></a>

  1107. (<em>posix_venv</em>, <em>nt_venv</em> and <em>venv</em>) were added and are used when Python

  1108. creates new virtual environments or when it is running from a virtual

  1109. environment.

  1110. The first two schemes (<em>posix_venv</em> and <em>nt_venv</em>) are OS-specific

  1111. for non-Windows and Windows, the <em>venv</em> is essentially an alias to one of

  1112. them according to the OS Python runs on.

  1113. This is useful for downstream distributors who modify

  1114. <a class="reference internal" href="../library/sysconfig.html#sysconfig.get_preferred_scheme" title="sysconfig.get_preferred_scheme"><code class="xref py py-func docutils literal notranslate"><span class="pre">sysconfig.get_preferred_scheme()</span></code></a>.

  1115. Third party code that creates new virtual environments should use the new

  1116. <em>venv</em> installation scheme to determine the paths, as does <a class="reference internal" href="../library/venv.html#module-venv" title="venv: Creation of virtual environments."><code class="xref py py-mod docutils literal notranslate"><span class="pre">venv</span></code></a>.

  1117. (Contributed by Miro Hrončok in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45413">bpo-45413</a>.)</p></li>

  1118. </ul>

  1119. </section>

  1120. <section id="tempfile">

  1121. <span id="whatsnew311-tempfile"></span><h3>tempfile<a class="headerlink" href="#tempfile" title="Link to this heading">¶</a></h3>

  1122. <ul class="simple">

  1123. <li><p><a class="reference internal" href="../library/tempfile.html#tempfile.SpooledTemporaryFile" title="tempfile.SpooledTemporaryFile"><code class="xref py py-class docutils literal notranslate"><span class="pre">SpooledTemporaryFile</span></code></a> objects now fully implement the methods

  1124. of <a class="reference internal" href="../library/io.html#io.BufferedIOBase" title="io.BufferedIOBase"><code class="xref py py-class docutils literal notranslate"><span class="pre">io.BufferedIOBase</span></code></a> or <a class="reference internal" href="../library/io.html#io.TextIOBase" title="io.TextIOBase"><code class="xref py py-class docutils literal notranslate"><span class="pre">io.TextIOBase</span></code></a>

  1125. (depending on file mode).

  1126. This lets them work correctly with APIs that expect file-like objects,

  1127. such as compression modules.

  1128. (Contributed by Carey Metcalfe in <a class="reference external" href="https://github.com/python/cpython/issues/70363">gh-70363</a>.)</p></li>

  1129. </ul>

  1130. </section>

  1131. <section id="threading">

  1132. <span id="whatsnew311-threading"></span><h3>threading<a class="headerlink" href="#threading" title="Link to this heading">¶</a></h3>

  1133. <ul class="simple">

  1134. <li><p>On Unix, if the <code class="docutils literal notranslate"><span class="pre">sem_clockwait()</span></code> function is available in the C library

  1135. (glibc 2.30 and newer), the <a class="reference internal" href="../library/threading.html#threading.Lock.acquire" title="threading.Lock.acquire"><code class="xref py py-meth docutils literal notranslate"><span class="pre">threading.Lock.acquire()</span></code></a> method now uses

  1136. the monotonic clock (<a class="reference internal" href="../library/time.html#time.CLOCK_MONOTONIC" title="time.CLOCK_MONOTONIC"><code class="xref py py-const docutils literal notranslate"><span class="pre">time.CLOCK_MONOTONIC</span></code></a>) for the timeout, rather

  1137. than using the system clock (<a class="reference internal" href="../library/time.html#time.CLOCK_REALTIME" title="time.CLOCK_REALTIME"><code class="xref py py-const docutils literal notranslate"><span class="pre">time.CLOCK_REALTIME</span></code></a>), to not be affected

  1138. by system clock changes.

  1139. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=41710">bpo-41710</a>.)</p></li>

  1140. </ul>

  1141. </section>

  1142. <section id="time">

  1143. <span id="whatsnew311-time"></span><h3>time<a class="headerlink" href="#time" title="Link to this heading">¶</a></h3>

  1144. <ul class="simple">

  1145. <li><p>On Unix, <a class="reference internal" href="../library/time.html#time.sleep" title="time.sleep"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.sleep()</span></code></a> now uses the <code class="docutils literal notranslate"><span class="pre">clock_nanosleep()</span></code> or

  1146. <code class="docutils literal notranslate"><span class="pre">nanosleep()</span></code> function, if available, which has a resolution of 1 nanosecond

  1147. (10<sup>-9</sup> seconds), rather than using <code class="docutils literal notranslate"><span class="pre">select()</span></code> which has a resolution

  1148. of 1 microsecond (10<sup>-6</sup> seconds).

  1149. (Contributed by Benjamin Szőke and Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=21302">bpo-21302</a>.)</p></li>

  1150. <li><p>On Windows 8.1 and newer, <a class="reference internal" href="../library/time.html#time.sleep" title="time.sleep"><code class="xref py py-func docutils literal notranslate"><span class="pre">time.sleep()</span></code></a> now uses a waitable timer based

  1151. on <a class="reference external" href="https://docs.microsoft.com/en-us/windows-hardware/drivers/kernel/high-resolution-timers">high-resolution timers</a>

  1152. which has a resolution of 100 nanoseconds (10<sup>-7</sup> seconds). Previously,

  1153. it had a resolution of 1 millisecond (10<sup>-3</sup> seconds).

  1154. (Contributed by Benjamin Szőke, Donghee Na, Eryk Sun and Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=21302">bpo-21302</a> and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45429">bpo-45429</a>.)</p></li>

  1155. </ul>

  1156. </section>

  1157. <section id="tkinter">

  1158. <span id="whatsnew311-tkinter"></span><h3>tkinter<a class="headerlink" href="#tkinter" title="Link to this heading">¶</a></h3>

  1159. <ul class="simple">

  1160. <li><p>Added method <code class="docutils literal notranslate"><span class="pre">info_patchlevel()</span></code> which returns the exact version of

  1161. the Tcl library as a named tuple similar to <a class="reference internal" href="../library/sys.html#sys.version_info" title="sys.version_info"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.version_info</span></code></a>.

  1162. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://github.com/python/cpython/issues/91827">gh-91827</a>.)</p></li>

  1163. </ul>

  1164. </section>

  1165. <section id="traceback">

  1166. <span id="whatsnew311-traceback"></span><h3>traceback<a class="headerlink" href="#traceback" title="Link to this heading">¶</a></h3>

  1167. <ul class="simple">

  1168. <li><p>Add <a class="reference internal" href="../library/traceback.html#traceback.StackSummary.format_frame_summary" title="traceback.StackSummary.format_frame_summary"><code class="xref py py-func docutils literal notranslate"><span class="pre">traceback.StackSummary.format_frame_summary()</span></code></a> to allow users

  1169. to override which frames appear in the traceback, and how they are

  1170. formatted.

  1171. (Contributed by Ammar Askar in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44569">bpo-44569</a>.)</p></li>

  1172. <li><p>Add <a class="reference internal" href="../library/traceback.html#traceback.TracebackException.print" title="traceback.TracebackException.print"><code class="xref py py-func docutils literal notranslate"><span class="pre">traceback.TracebackException.print()</span></code></a>, which prints the

  1173. formatted <a class="reference internal" href="../library/traceback.html#traceback.TracebackException" title="traceback.TracebackException"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TracebackException</span></code></a> instance to a file.

  1174. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=33809">bpo-33809</a>.)</p></li>

  1175. </ul>

  1176. </section>

  1177. <section id="typing">

  1178. <span id="whatsnew311-typing"></span><h3>typing<a class="headerlink" href="#typing" title="Link to this heading">¶</a></h3>

  1179. <p>For major changes, see <a class="reference internal" href="#new-feat-related-type-hints-311"><span class="std std-ref">New Features Related to Type Hints</span></a>.</p>

  1180. <ul class="simple">

  1181. <li><p>Add <a class="reference internal" href="../library/typing.html#typing.assert_never" title="typing.assert_never"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.assert_never()</span></code></a> and <a class="reference internal" href="../library/typing.html#typing.Never" title="typing.Never"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.Never</span></code></a>.

  1182. <a class="reference internal" href="../library/typing.html#typing.assert_never" title="typing.assert_never"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.assert_never()</span></code></a> is useful for asking a type checker to confirm

  1183. that a line of code is not reachable. At runtime, it raises an

  1184. <a class="reference internal" href="../library/exceptions.html#AssertionError" title="AssertionError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">AssertionError</span></code></a>.

  1185. (Contributed by Jelle Zijlstra in <a class="reference external" href="https://github.com/python/cpython/issues/90633">gh-90633</a>.)</p></li>

  1186. <li><p>Add <a class="reference internal" href="../library/typing.html#typing.reveal_type" title="typing.reveal_type"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.reveal_type()</span></code></a>. This is useful for asking a type checker

  1187. what type it has inferred for a given expression. At runtime it prints

  1188. the type of the received value.

  1189. (Contributed by Jelle Zijlstra in <a class="reference external" href="https://github.com/python/cpython/issues/90572">gh-90572</a>.)</p></li>

  1190. <li><p>Add <a class="reference internal" href="../library/typing.html#typing.assert_type" title="typing.assert_type"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.assert_type()</span></code></a>. This is useful for asking a type checker

  1191. to confirm that the type it has inferred for a given expression matches

  1192. the given type. At runtime it simply returns the received value.

  1193. (Contributed by Jelle Zijlstra in <a class="reference external" href="https://github.com/python/cpython/issues/90638">gh-90638</a>.)</p></li>

  1194. <li><p><a class="reference internal" href="../library/typing.html#typing.TypedDict" title="typing.TypedDict"><code class="xref py py-data docutils literal notranslate"><span class="pre">typing.TypedDict</span></code></a> types can now be generic. (Contributed by

  1195. Samodya Abeysiriwardane in <a class="reference external" href="https://github.com/python/cpython/issues/89026">gh-89026</a>.)</p></li>

  1196. <li><p><a class="reference internal" href="../library/typing.html#typing.NamedTuple" title="typing.NamedTuple"><code class="xref py py-class docutils literal notranslate"><span class="pre">NamedTuple</span></code></a> types can now be generic.

  1197. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43923">bpo-43923</a>.)</p></li>

  1198. <li><p>Allow subclassing of <a class="reference internal" href="../library/typing.html#typing.Any" title="typing.Any"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.Any</span></code></a>. This is useful for avoiding

  1199. type checker errors related to highly dynamic class, such as mocks.

  1200. (Contributed by Shantanu Jain in <a class="reference external" href="https://github.com/python/cpython/issues/91154">gh-91154</a>.)</p></li>

  1201. <li><p>The <a class="reference internal" href="../library/typing.html#typing.final" title="typing.final"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.final()</span></code></a> decorator now sets the <code class="docutils literal notranslate"><span class="pre">__final__</span></code> attributed on

  1202. the decorated object.

  1203. (Contributed by Jelle Zijlstra in <a class="reference external" href="https://github.com/python/cpython/issues/90500">gh-90500</a>.)</p></li>

  1204. <li><p>The <a class="reference internal" href="../library/typing.html#typing.get_overloads" title="typing.get_overloads"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.get_overloads()</span></code></a> function can be used for introspecting

  1205. the overloads of a function. <a class="reference internal" href="../library/typing.html#typing.clear_overloads" title="typing.clear_overloads"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.clear_overloads()</span></code></a> can be used

  1206. to clear all registered overloads of a function.

  1207. (Contributed by Jelle Zijlstra in <a class="reference external" href="https://github.com/python/cpython/issues/89263">gh-89263</a>.)</p></li>

  1208. <li><p>The <a class="reference internal" href="../reference/datamodel.html#object.__init__" title="object.__init__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__init__()</span></code></a> method of <a class="reference internal" href="../library/typing.html#typing.Protocol" title="typing.Protocol"><code class="xref py py-class docutils literal notranslate"><span class="pre">Protocol</span></code></a> subclasses

  1209. is now preserved. (Contributed by Adrian Garcia Badarasco in <a class="reference external" href="https://github.com/python/cpython/issues/88970">gh-88970</a>.)</p></li>

  1210. <li><p>The representation of empty tuple types (<code class="docutils literal notranslate"><span class="pre">Tuple[()]</span></code>) is simplified.

  1211. This affects introspection, e.g. <code class="docutils literal notranslate"><span class="pre">get_args(Tuple[()])</span></code> now evaluates

  1212. to <code class="docutils literal notranslate"><span class="pre">()</span></code> instead of <code class="docutils literal notranslate"><span class="pre">((),)</span></code>.

  1213. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://github.com/python/cpython/issues/91137">gh-91137</a>.)</p></li>

  1214. <li><p>Loosen runtime requirements for type annotations by removing the callable

  1215. check in the private <code class="docutils literal notranslate"><span class="pre">typing._type_check</span></code> function. (Contributed by

  1216. Gregory Beauregard in <a class="reference external" href="https://github.com/python/cpython/issues/90802">gh-90802</a>.)</p></li>

  1217. <li><p><a class="reference internal" href="../library/typing.html#typing.get_type_hints" title="typing.get_type_hints"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.get_type_hints()</span></code></a> now supports evaluating strings as forward

  1218. references in <a class="reference internal" href="../library/stdtypes.html#types-genericalias"><span class="std std-ref">PEP 585 generic aliases</span></a>.

  1219. (Contributed by Niklas Rosenstein in <a class="reference external" href="https://github.com/python/cpython/issues/85542">gh-85542</a>.)</p></li>

  1220. <li><p><a class="reference internal" href="../library/typing.html#typing.get_type_hints" title="typing.get_type_hints"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.get_type_hints()</span></code></a> no longer adds <a class="reference internal" href="../library/typing.html#typing.Optional" title="typing.Optional"><code class="xref py py-data docutils literal notranslate"><span class="pre">Optional</span></code></a>

  1221. to parameters with <code class="docutils literal notranslate"><span class="pre">None</span></code> as a default. (Contributed by Nikita Sobolev

  1222. in <a class="reference external" href="https://github.com/python/cpython/issues/90353">gh-90353</a>.)</p></li>

  1223. <li><p><a class="reference internal" href="../library/typing.html#typing.get_type_hints" title="typing.get_type_hints"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.get_type_hints()</span></code></a> now supports evaluating bare stringified

  1224. <a class="reference internal" href="../library/typing.html#typing.ClassVar" title="typing.ClassVar"><code class="xref py py-data docutils literal notranslate"><span class="pre">ClassVar</span></code></a> annotations. (Contributed by Gregory Beauregard

  1225. in <a class="reference external" href="https://github.com/python/cpython/issues/90711">gh-90711</a>.)</p></li>

  1226. <li><p><a class="reference internal" href="../library/typing.html#typing.no_type_check" title="typing.no_type_check"><code class="xref py py-func docutils literal notranslate"><span class="pre">typing.no_type_check()</span></code></a> no longer modifies external classes and functions.

  1227. It also now correctly marks classmethods as not to be type checked. (Contributed

  1228. by Nikita Sobolev in <a class="reference external" href="https://github.com/python/cpython/issues/90729">gh-90729</a>.)</p></li>

  1229. </ul>

  1230. </section>

  1231. <section id="unicodedata">

  1232. <span id="whatsnew311-unicodedata"></span><h3>unicodedata<a class="headerlink" href="#unicodedata" title="Link to this heading">¶</a></h3>

  1233. <ul class="simple">

  1234. <li><p>The Unicode database has been updated to version 14.0.0.

  1235. (Contributed by Benjamin Peterson in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45190">bpo-45190</a>).</p></li>

  1236. </ul>

  1237. </section>

  1238. <section id="unittest">

  1239. <span id="whatsnew311-unittest"></span><h3>unittest<a class="headerlink" href="#unittest" title="Link to this heading">¶</a></h3>

  1240. <ul class="simple">

  1241. <li><p>Added methods <a class="reference internal" href="../library/unittest.html#unittest.TestCase.enterContext" title="unittest.TestCase.enterContext"><code class="xref py py-meth docutils literal notranslate"><span class="pre">enterContext()</span></code></a> and

  1242. <a class="reference internal" href="../library/unittest.html#unittest.TestCase.enterClassContext" title="unittest.TestCase.enterClassContext"><code class="xref py py-meth docutils literal notranslate"><span class="pre">enterClassContext()</span></code></a> of class

  1243. <a class="reference internal" href="../library/unittest.html#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a>, method

  1244. <a class="reference internal" href="../library/unittest.html#unittest.IsolatedAsyncioTestCase.enterAsyncContext" title="unittest.IsolatedAsyncioTestCase.enterAsyncContext"><code class="xref py py-meth docutils literal notranslate"><span class="pre">enterAsyncContext()</span></code></a> of

  1245. class <a class="reference internal" href="../library/unittest.html#unittest.IsolatedAsyncioTestCase" title="unittest.IsolatedAsyncioTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">IsolatedAsyncioTestCase</span></code></a> and function

  1246. <a class="reference internal" href="../library/unittest.html#unittest.enterModuleContext" title="unittest.enterModuleContext"><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.enterModuleContext()</span></code></a>.

  1247. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45046">bpo-45046</a>.)</p></li>

  1248. </ul>

  1249. </section>

  1250. <section id="venv">

  1251. <span id="whatsnew311-venv"></span><h3>venv<a class="headerlink" href="#venv" title="Link to this heading">¶</a></h3>

  1252. <ul class="simple">

  1253. <li><p>When new Python virtual environments are created, the <em>venv</em>

  1254. <a class="reference internal" href="../library/sysconfig.html#installation-paths"><span class="std std-ref">sysconfig installation scheme</span></a> is used

  1255. to determine the paths inside the environment.

  1256. When Python runs in a virtual environment, the same installation scheme

  1257. is the default.

  1258. That means that downstream distributors can change the default sysconfig install

  1259. scheme without changing behavior of virtual environments.

  1260. Third party code that also creates new virtual environments should do the same.

  1261. (Contributed by Miro Hrončok in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45413">bpo-45413</a>.)</p></li>

  1262. </ul>

  1263. </section>

  1264. <section id="warnings">

  1265. <span id="whatsnew311-warnings"></span><h3>warnings<a class="headerlink" href="#warnings" title="Link to this heading">¶</a></h3>

  1266. <ul class="simple">

  1267. <li><p><a class="reference internal" href="../library/warnings.html#warnings.catch_warnings" title="warnings.catch_warnings"><code class="xref py py-func docutils literal notranslate"><span class="pre">warnings.catch_warnings()</span></code></a> now accepts arguments for <a class="reference internal" href="../library/warnings.html#warnings.simplefilter" title="warnings.simplefilter"><code class="xref py py-func docutils literal notranslate"><span class="pre">warnings.simplefilter()</span></code></a>,

  1268. providing a more concise way to locally ignore warnings or convert them to errors.

  1269. (Contributed by Zac Hatfield-Dodds in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47074">bpo-47074</a>.)</p></li>

  1270. </ul>

  1271. </section>

  1272. <section id="zipfile">

  1273. <span id="whatsnew311-zipfile"></span><h3>zipfile<a class="headerlink" href="#zipfile" title="Link to this heading">¶</a></h3>

  1274. <ul class="simple">

  1275. <li><p>Added support for specifying member name encoding for reading metadata

  1276. in a <a class="reference internal" href="../library/zipfile.html#zipfile.ZipFile" title="zipfile.ZipFile"><code class="xref py py-class docutils literal notranslate"><span class="pre">ZipFile</span></code></a>’s directory and file headers.

  1277. (Contributed by Stephen J. Turnbull and Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=28080">bpo-28080</a>.)</p></li>

  1278. <li><p>Added <a class="reference internal" href="../library/zipfile.html#zipfile.ZipFile.mkdir" title="zipfile.ZipFile.mkdir"><code class="xref py py-meth docutils literal notranslate"><span class="pre">ZipFile.mkdir()</span></code></a>

  1279. for creating new directories inside ZIP archives.

  1280. (Contributed by Sam Ezeh in <a class="reference external" href="https://github.com/python/cpython/issues/49083">gh-49083</a>.)</p></li>

  1281. <li><p>Added <a class="reference internal" href="../library/zipfile.html#zipfile.Path.stem" title="zipfile.Path.stem"><code class="xref py py-attr docutils literal notranslate"><span class="pre">stem</span></code></a>, <a class="reference internal" href="../library/zipfile.html#zipfile.Path.suffix" title="zipfile.Path.suffix"><code class="xref py py-attr docutils literal notranslate"><span class="pre">suffix</span></code></a>

  1282. and <a class="reference internal" href="../library/zipfile.html#zipfile.Path.suffixes" title="zipfile.Path.suffixes"><code class="xref py py-attr docutils literal notranslate"><span class="pre">suffixes</span></code></a> to <a class="reference internal" href="../library/zipfile.html#zipfile.Path" title="zipfile.Path"><code class="xref py py-class docutils literal notranslate"><span class="pre">zipfile.Path</span></code></a>.

  1283. (Contributed by Miguel Brito in <a class="reference external" href="https://github.com/python/cpython/issues/88261">gh-88261</a>.)</p></li>

  1284. </ul>

  1285. </section>

  1286. </section>

  1287. <section id="optimizations">

  1288. <span id="whatsnew311-optimizations"></span><h2>Optimizations<a class="headerlink" href="#optimizations" title="Link to this heading">¶</a></h2>

  1289. <p>This section covers specific optimizations independent of the

  1290. <a class="reference internal" href="#whatsnew311-faster-cpython"><span class="std std-ref">Faster CPython</span></a> project, which is covered in its own section.</p>

  1291. <ul class="simple">

  1292. <li><p>The compiler now optimizes simple

  1293. <a class="reference internal" href="../library/stdtypes.html#old-string-formatting"><span class="std std-ref">printf-style % formatting</span></a> on string literals

  1294. containing only the format codes <code class="docutils literal notranslate"><span class="pre">%s</span></code>, <code class="docutils literal notranslate"><span class="pre">%r</span></code> and <code class="docutils literal notranslate"><span class="pre">%a</span></code> and makes it as

  1295. fast as a corresponding <a class="reference internal" href="../glossary.html#term-f-string"><span class="xref std std-term">f-string</span></a> expression.

  1296. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=28307">bpo-28307</a>.)</p></li>

  1297. <li><p>Integer division (<code class="docutils literal notranslate"><span class="pre">//</span></code>) is better tuned for optimization by compilers.

  1298. It is now around 20% faster on x86-64 when dividing an <a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate"><span class="pre">int</span></code></a>

  1299. by a value smaller than <code class="docutils literal notranslate"><span class="pre">2**30</span></code>.

  1300. (Contributed by Gregory P. Smith and Tim Peters in <a class="reference external" href="https://github.com/python/cpython/issues/90564">gh-90564</a>.)</p></li>

  1301. <li><p><a class="reference internal" href="../library/functions.html#sum" title="sum"><code class="xref py py-func docutils literal notranslate"><span class="pre">sum()</span></code></a> is now nearly 30% faster for integers smaller than <code class="docutils literal notranslate"><span class="pre">2**30</span></code>.

  1302. (Contributed by Stefan Behnel in <a class="reference external" href="https://github.com/python/cpython/issues/68264">gh-68264</a>.)</p></li>

  1303. <li><p>Resizing lists is streamlined for the common case,

  1304. speeding up <code class="xref py py-meth docutils literal notranslate"><span class="pre">list.append()</span></code> by ≈15%

  1305. and simple <a class="reference internal" href="../glossary.html#term-list-comprehension"><span class="xref std std-term">list comprehension</span></a>s by up to 20-30%

  1306. (Contributed by Dennis Sweeney in <a class="reference external" href="https://github.com/python/cpython/issues/91165">gh-91165</a>.)</p></li>

  1307. <li><p>Dictionaries don’t store hash values when all keys are Unicode objects,

  1308. decreasing <a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate"><span class="pre">dict</span></code></a> size.

  1309. For example, <code class="docutils literal notranslate"><span class="pre">sys.getsizeof(dict.fromkeys(&quot;abcdefg&quot;))</span></code>

  1310. is reduced from 352 bytes to 272 bytes (23% smaller) on 64-bit platforms.

  1311. (Contributed by Inada Naoki in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46845">bpo-46845</a>.)</p></li>

  1312. <li><p>Using <a class="reference internal" href="../library/asyncio-protocol.html#asyncio.DatagramProtocol" title="asyncio.DatagramProtocol"><code class="xref py py-class docutils literal notranslate"><span class="pre">asyncio.DatagramProtocol</span></code></a> is now orders of magnitude faster

  1313. when transferring large files over UDP,

  1314. with speeds over 100 times higher for a ≈60 MiB file.

  1315. (Contributed by msoxzw in <a class="reference external" href="https://github.com/python/cpython/issues/91487">gh-91487</a>.)</p></li>

  1316. <li><p><a class="reference internal" href="../library/math.html#module-math" title="math: Mathematical functions (sin() etc.)."><code class="xref py py-mod docutils literal notranslate"><span class="pre">math</span></code></a> functions <a class="reference internal" href="../library/math.html#math.comb" title="math.comb"><code class="xref py py-func docutils literal notranslate"><span class="pre">comb()</span></code></a> and <a class="reference internal" href="../library/math.html#math.perm" title="math.perm"><code class="xref py py-func docutils literal notranslate"><span class="pre">perm()</span></code></a> are now

  1317. ≈10 times faster for large arguments (with a larger speedup for larger <em>k</em>).

  1318. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=37295">bpo-37295</a>.)</p></li>

  1319. <li><p>The <a class="reference internal" href="../library/statistics.html#module-statistics" title="statistics: Mathematical statistics functions"><code class="xref py py-mod docutils literal notranslate"><span class="pre">statistics</span></code></a> functions <a class="reference internal" href="../library/statistics.html#statistics.mean" title="statistics.mean"><code class="xref py py-func docutils literal notranslate"><span class="pre">mean()</span></code></a>,

  1320. <a class="reference internal" href="../library/statistics.html#statistics.variance" title="statistics.variance"><code class="xref py py-func docutils literal notranslate"><span class="pre">variance()</span></code></a> and <a class="reference internal" href="../library/statistics.html#statistics.stdev" title="statistics.stdev"><code class="xref py py-func docutils literal notranslate"><span class="pre">stdev()</span></code></a> now consume

  1321. iterators in one pass rather than converting them to a <a class="reference internal" href="../library/stdtypes.html#list" title="list"><code class="xref py py-class docutils literal notranslate"><span class="pre">list</span></code></a> first.

  1322. This is twice as fast and can save substantial memory.

  1323. (Contributed by Raymond Hettinger in <a class="reference external" href="https://github.com/python/cpython/issues/90415">gh-90415</a>.)</p></li>

  1324. <li><p><a class="reference internal" href="../library/unicodedata.html#unicodedata.normalize" title="unicodedata.normalize"><code class="xref py py-func docutils literal notranslate"><span class="pre">unicodedata.normalize()</span></code></a>

  1325. now normalizes pure-ASCII strings in constant time.

  1326. (Contributed by Donghee Na in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44987">bpo-44987</a>.)</p></li>

  1327. </ul>

  1328. </section>

  1329. <section id="faster-cpython">

  1330. <span id="whatsnew311-faster-cpython"></span><h2>Faster CPython<a class="headerlink" href="#faster-cpython" title="Link to this heading">¶</a></h2>

  1331. <p>CPython 3.11 is an average of

  1332. <a class="reference external" href="https://github.com/faster-cpython/ideas#published-results">25% faster</a>

  1333. than CPython 3.10 as measured with the

  1334. <a class="reference external" href="https://github.com/python/pyperformance">pyperformance</a> benchmark suite,

  1335. when compiled with GCC on Ubuntu Linux.

  1336. Depending on your workload, the overall speedup could be 10-60%.</p>

  1337. <p>This project focuses on two major areas in Python:

  1338. <a class="reference internal" href="#whatsnew311-faster-startup"><span class="std std-ref">Faster Startup</span></a> and <a class="reference internal" href="#whatsnew311-faster-runtime"><span class="std std-ref">Faster Runtime</span></a>.

  1339. Optimizations not covered by this project are listed separately under

  1340. <a class="reference internal" href="#whatsnew311-optimizations"><span class="std std-ref">Optimizations</span></a>.</p>

  1341. <section id="faster-startup">

  1342. <span id="whatsnew311-faster-startup"></span><h3>Faster Startup<a class="headerlink" href="#faster-startup" title="Link to this heading">¶</a></h3>

  1343. <section id="frozen-imports-static-code-objects">

  1344. <span id="whatsnew311-faster-imports"></span><h4>Frozen imports / Static code objects<a class="headerlink" href="#frozen-imports-static-code-objects" title="Link to this heading">¶</a></h4>

  1345. <p>Python caches <a class="reference internal" href="../glossary.html#term-bytecode"><span class="xref std std-term">bytecode</span></a> in the <a class="reference internal" href="../tutorial/modules.html#tut-pycache"><span class="std std-ref">__pycache__</span></a>

  1346. directory to speed up module loading.</p>

  1347. <p>Previously in 3.10, Python module execution looked like this:</p>

  1348. <div class="highlight-text notranslate"><div class="highlight"><pre><span></span>Read __pycache__ -&gt; Unmarshal -&gt; Heap allocated code object -&gt; Evaluate

  1349. </pre></div>

  1350. </div>

  1351. <p>In Python 3.11, the core modules essential for Python startup are “frozen”.

  1352. This means that their <a class="reference internal" href="../c-api/code.html#codeobjects"><span class="std std-ref">Code Objects</span></a> (and bytecode)

  1353. are statically allocated by the interpreter.

  1354. This reduces the steps in module execution process to:</p>

  1355. <div class="highlight-text notranslate"><div class="highlight"><pre><span></span>Statically allocated code object -&gt; Evaluate

  1356. </pre></div>

  1357. </div>

  1358. <p>Interpreter startup is now 10-15% faster in Python 3.11. This has a big

  1359. impact for short-running programs using Python.</p>

  1360. <p>(Contributed by Eric Snow, Guido van Rossum and Kumar Aditya in many issues.)</p>

  1361. </section>

  1362. </section>

  1363. <section id="faster-runtime">

  1364. <span id="whatsnew311-faster-runtime"></span><h3>Faster Runtime<a class="headerlink" href="#faster-runtime" title="Link to this heading">¶</a></h3>

  1365. <section id="cheaper-lazy-python-frames">

  1366. <span id="whatsnew311-lazy-python-frames"></span><h4>Cheaper, lazy Python frames<a class="headerlink" href="#cheaper-lazy-python-frames" title="Link to this heading">¶</a></h4>

  1367. <p>Python frames, holding execution information,

  1368. are created whenever Python calls a Python function.

  1369. The following are new frame optimizations:</p>

  1370. <ul class="simple">

  1371. <li><p>Streamlined the frame creation process.</p></li>

  1372. <li><p>Avoided memory allocation by generously re-using frame space on the C stack.</p></li>

  1373. <li><p>Streamlined the internal frame struct to contain only essential information.

  1374. Frames previously held extra debugging and memory management information.</p></li>

  1375. </ul>

  1376. <p>Old-style <a class="reference internal" href="../reference/datamodel.html#frame-objects"><span class="std std-ref">frame objects</span></a>

  1377. are now created only when requested by debuggers

  1378. or by Python introspection functions such as <a class="reference internal" href="../library/sys.html#sys._getframe" title="sys._getframe"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys._getframe()</span></code></a> and

  1379. <a class="reference internal" href="../library/inspect.html#inspect.currentframe" title="inspect.currentframe"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.currentframe()</span></code></a>. For most user code, no frame objects are

  1380. created at all. As a result, nearly all Python functions calls have sped

  1381. up significantly. We measured a 3-7% speedup in pyperformance.</p>

  1382. <p>(Contributed by Mark Shannon in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44590">bpo-44590</a>.)</p>

  1383. </section>

  1384. <section id="inlined-python-function-calls">

  1385. <span id="whatsnew311-inline-calls"></span><span id="inline-calls"></span><h4>Inlined Python function calls<a class="headerlink" href="#inlined-python-function-calls" title="Link to this heading">¶</a></h4>

  1386. <p>During a Python function call, Python will call an evaluating C function to

  1387. interpret that function’s code. This effectively limits pure Python recursion to

  1388. what’s safe for the C stack.</p>

  1389. <p>In 3.11, when CPython detects Python code calling another Python function,

  1390. it sets up a new frame, and “jumps” to the new code inside the new frame. This

  1391. avoids calling the C interpreting function altogether.</p>

  1392. <p>Most Python function calls now consume no C stack space, speeding them up.

  1393. In simple recursive functions like fibonacci or

  1394. factorial, we observed a 1.7x speedup. This also means recursive functions

  1395. can recurse significantly deeper

  1396. (if the user increases the recursion limit with <a class="reference internal" href="../library/sys.html#sys.setrecursionlimit" title="sys.setrecursionlimit"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.setrecursionlimit()</span></code></a>).

  1397. We measured a 1-3% improvement in pyperformance.</p>

  1398. <p>(Contributed by Pablo Galindo and Mark Shannon in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45256">bpo-45256</a>.)</p>

  1399. </section>

  1400. <section id="pep-659-specializing-adaptive-interpreter">

  1401. <span id="whatsnew311-pep659"></span><h4>PEP 659: Specializing Adaptive Interpreter<a class="headerlink" href="#pep-659-specializing-adaptive-interpreter" title="Link to this heading">¶</a></h4>

  1402. <p><span class="target" id="index-28"></span><a class="pep reference external" href="https://peps.python.org/pep-0659/"><strong>PEP 659</strong></a> is one of the key parts of the Faster CPython project. The general

  1403. idea is that while Python is a dynamic language, most code has regions where

  1404. objects and types rarely change. This concept is known as <em>type stability</em>.</p>

  1405. <p>At runtime, Python will try to look for common patterns and type stability

  1406. in the executing code. Python will then replace the current operation with a

  1407. more specialized one. This specialized operation uses fast paths available only

  1408. to those use cases/types, which generally outperform their generic

  1409. counterparts. This also brings in another concept called <em>inline caching</em>, where

  1410. Python caches the results of expensive operations directly in the

  1411. <a class="reference internal" href="../glossary.html#term-bytecode"><span class="xref std std-term">bytecode</span></a>.</p>

  1412. <p>The specializer will also combine certain common instruction pairs into one

  1413. superinstruction, reducing the overhead during execution.</p>

  1414. <p>Python will only specialize

  1415. when it sees code that is “hot” (executed multiple times). This prevents Python

  1416. from wasting time on run-once code. Python can also de-specialize when code is

  1417. too dynamic or when the use changes. Specialization is attempted periodically,

  1418. and specialization attempts are not too expensive,

  1419. allowing specialization to adapt to new circumstances.</p>

  1420. <p>(PEP written by Mark Shannon, with ideas inspired by Stefan Brunthaler.

  1421. See <span class="target" id="index-29"></span><a class="pep reference external" href="https://peps.python.org/pep-0659/"><strong>PEP 659</strong></a> for more information. Implementation by Mark Shannon and Brandt

  1422. Bucher, with additional help from Irit Katriel and Dennis Sweeney.)</p>

  1423. <table class="docutils align-default">

  1424. <thead>

  1425. <tr class="row-odd"><th class="head"><p>Operation</p></th>

  1426. <th class="head"><p>Form</p></th>

  1427. <th class="head"><p>Specialization</p></th>

  1428. <th class="head"><p>Operation speedup

  1429. (up to)</p></th>

  1430. <th class="head"><p>Contributor(s)</p></th>

  1431. </tr>

  1432. </thead>

  1433. <tbody>

  1434. <tr class="row-even"><td><p>Binary

  1435. operations</p></td>

  1436. <td><p><code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre">+</span> <span class="pre">x</span></code></p>

  1437. <p><code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre">-</span> <span class="pre">x</span></code></p>

  1438. <p><code class="docutils literal notranslate"><span class="pre">x</span> <span class="pre">*</span> <span class="pre">x</span></code></p>

  1439. </td>

  1440. <td><p>Binary add, multiply and subtract for common types

  1441. such as <a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate"><span class="pre">int</span></code></a>, <a class="reference internal" href="../library/functions.html#float" title="float"><code class="xref py py-class docutils literal notranslate"><span class="pre">float</span></code></a> and <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a>

  1442. take custom fast paths for their underlying types.</p></td>

  1443. <td><p>10%</p></td>

  1444. <td><p>Mark Shannon,

  1445. Donghee Na,

  1446. Brandt Bucher,

  1447. Dennis Sweeney</p></td>

  1448. </tr>

  1449. <tr class="row-odd"><td><p>Subscript</p></td>

  1450. <td><p><code class="docutils literal notranslate"><span class="pre">a[i]</span></code></p></td>

  1451. <td><p>Subscripting container types such as <a class="reference internal" href="../library/stdtypes.html#list" title="list"><code class="xref py py-class docutils literal notranslate"><span class="pre">list</span></code></a>,

  1452. <a class="reference internal" href="../library/stdtypes.html#tuple" title="tuple"><code class="xref py py-class docutils literal notranslate"><span class="pre">tuple</span></code></a> and <a class="reference internal" href="../library/stdtypes.html#dict" title="dict"><code class="xref py py-class docutils literal notranslate"><span class="pre">dict</span></code></a> directly index

  1453. the underlying data structures.</p>

  1454. <p>Subscripting custom <a class="reference internal" href="../reference/datamodel.html#object.__getitem__" title="object.__getitem__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__getitem__()</span></code></a>

  1455. is also inlined similar to <a class="reference internal" href="#inline-calls"><span class="std std-ref">Inlined Python function calls</span></a>.</p>

  1456. </td>

  1457. <td><p>10-25%</p></td>

  1458. <td><p>Irit Katriel,

  1459. Mark Shannon</p></td>

  1460. </tr>

  1461. <tr class="row-even"><td><p>Store

  1462. subscript</p></td>

  1463. <td><p><code class="docutils literal notranslate"><span class="pre">a[i]</span> <span class="pre">=</span> <span class="pre">z</span></code></p></td>

  1464. <td><p>Similar to subscripting specialization above.</p></td>

  1465. <td><p>10-25%</p></td>

  1466. <td><p>Dennis Sweeney</p></td>

  1467. </tr>

  1468. <tr class="row-odd"><td><p>Calls</p></td>

  1469. <td><p><code class="docutils literal notranslate"><span class="pre">f(arg)</span></code></p>

  1470. <p><code class="docutils literal notranslate"><span class="pre">C(arg)</span></code></p>

  1471. </td>

  1472. <td><p>Calls to common builtin (C) functions and types such

  1473. as <a class="reference internal" href="../library/functions.html#len" title="len"><code class="xref py py-func docutils literal notranslate"><span class="pre">len()</span></code></a> and <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a> directly call their

  1474. underlying C version. This avoids going through the

  1475. internal calling convention.</p></td>

  1476. <td><p>20%</p></td>

  1477. <td><p>Mark Shannon,

  1478. Ken Jin</p></td>

  1479. </tr>

  1480. <tr class="row-even"><td><p>Load

  1481. global

  1482. variable</p></td>

  1483. <td><p><code class="docutils literal notranslate"><span class="pre">print</span></code></p>

  1484. <p><code class="docutils literal notranslate"><span class="pre">len</span></code></p>

  1485. </td>

  1486. <td><p>The object’s index in the globals/builtins namespace

  1487. is cached. Loading globals and builtins require

  1488. zero namespace lookups.</p></td>

  1489. <td><p><a class="footnote-reference brackets" href="#load-global" id="id2" role="doc-noteref"><span class="fn-bracket">[</span>1<span class="fn-bracket">]</span></a></p></td>

  1490. <td><p>Mark Shannon</p></td>

  1491. </tr>

  1492. <tr class="row-odd"><td><p>Load

  1493. attribute</p></td>

  1494. <td><p><code class="docutils literal notranslate"><span class="pre">o.attr</span></code></p></td>

  1495. <td><p>Similar to loading global variables. The attribute’s

  1496. index inside the class/object’s namespace is cached.

  1497. In most cases, attribute loading will require zero

  1498. namespace lookups.</p></td>

  1499. <td><p><a class="footnote-reference brackets" href="#load-attr" id="id3" role="doc-noteref"><span class="fn-bracket">[</span>2<span class="fn-bracket">]</span></a></p></td>

  1500. <td><p>Mark Shannon</p></td>

  1501. </tr>

  1502. <tr class="row-even"><td><p>Load

  1503. methods for

  1504. call</p></td>

  1505. <td><p><code class="docutils literal notranslate"><span class="pre">o.meth()</span></code></p></td>

  1506. <td><p>The actual address of the method is cached. Method

  1507. loading now has no namespace lookups – even for

  1508. classes with long inheritance chains.</p></td>

  1509. <td><p>10-20%</p></td>

  1510. <td><p>Ken Jin,

  1511. Mark Shannon</p></td>

  1512. </tr>

  1513. <tr class="row-odd"><td><p>Store

  1514. attribute</p></td>

  1515. <td><p><code class="docutils literal notranslate"><span class="pre">o.attr</span> <span class="pre">=</span> <span class="pre">z</span></code></p></td>

  1516. <td><p>Similar to load attribute optimization.</p></td>

  1517. <td><p>2%

  1518. in pyperformance</p></td>

  1519. <td><p>Mark Shannon</p></td>

  1520. </tr>

  1521. <tr class="row-even"><td><p>Unpack

  1522. Sequence</p></td>

  1523. <td><p><code class="docutils literal notranslate"><span class="pre">*seq</span></code></p></td>

  1524. <td><p>Specialized for common containers such as

  1525. <a class="reference internal" href="../library/stdtypes.html#list" title="list"><code class="xref py py-class docutils literal notranslate"><span class="pre">list</span></code></a> and <a class="reference internal" href="../library/stdtypes.html#tuple" title="tuple"><code class="xref py py-class docutils literal notranslate"><span class="pre">tuple</span></code></a>.

  1526. Avoids internal calling convention.</p></td>

  1527. <td><p>8%</p></td>

  1528. <td><p>Brandt Bucher</p></td>

  1529. </tr>

  1530. </tbody>

  1531. </table>

  1532. <aside class="footnote-list brackets">

  1533. <aside class="footnote brackets" id="load-global" role="doc-footnote">

  1534. <span class="label"><span class="fn-bracket">[</span><a role="doc-backlink" href="#id2">1</a><span class="fn-bracket">]</span></span>

  1535. <p>A similar optimization already existed since Python 3.8.

  1536. 3.11 specializes for more forms and reduces some overhead.</p>

  1537. </aside>

  1538. <aside class="footnote brackets" id="load-attr" role="doc-footnote">

  1539. <span class="label"><span class="fn-bracket">[</span><a role="doc-backlink" href="#id3">2</a><span class="fn-bracket">]</span></span>

  1540. <p>A similar optimization already existed since Python 3.10.

  1541. 3.11 specializes for more forms. Furthermore, all attribute loads should

  1542. be sped up by <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45947">bpo-45947</a>.</p>

  1543. </aside>

  1544. </aside>

  1545. </section>

  1546. </section>

  1547. <section id="misc">

  1548. <span id="whatsnew311-faster-cpython-misc"></span><h3>Misc<a class="headerlink" href="#misc" title="Link to this heading">¶</a></h3>

  1549. <ul class="simple">

  1550. <li><p>Objects now require less memory due to lazily created object namespaces.

  1551. Their namespace dictionaries now also share keys more freely.

  1552. (Contributed Mark Shannon in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45340">bpo-45340</a> and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40116">bpo-40116</a>.)</p></li>

  1553. <li><p>“Zero-cost” exceptions are implemented, eliminating the cost

  1554. of <a class="reference internal" href="../reference/compound_stmts.html#try"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">try</span></code></a> statements when no exception is raised.

  1555. (Contributed by Mark Shannon in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40222">bpo-40222</a>.)</p></li>

  1556. <li><p>A more concise representation of exceptions in the interpreter reduced the

  1557. time required for catching an exception by about 10%.

  1558. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45711">bpo-45711</a>.)</p></li>

  1559. <li><p><a class="reference internal" href="../library/re.html#module-re" title="re: Regular expression operations."><code class="xref py py-mod docutils literal notranslate"><span class="pre">re</span></code></a>’s regular expression matching engine has been partially refactored,

  1560. and now uses computed gotos (or “threaded code”) on supported platforms. As a

  1561. result, Python 3.11 executes the <a class="reference external" href="https://pyperformance.readthedocs.io/benchmarks.html#regex-dna">pyperformance regular expression benchmarks</a> up to 10%

  1562. faster than Python 3.10.

  1563. (Contributed by Brandt Bucher in <a class="reference external" href="https://github.com/python/cpython/issues/91404">gh-91404</a>.)</p></li>

  1564. </ul>

  1565. </section>

  1566. <section id="faq">

  1567. <span id="whatsnew311-faster-cpython-faq"></span><h3>FAQ<a class="headerlink" href="#faq" title="Link to this heading">¶</a></h3>

  1568. <section id="how-should-i-write-my-code-to-utilize-these-speedups">

  1569. <span id="faster-cpython-faq-my-code"></span><h4>How should I write my code to utilize these speedups?<a class="headerlink" href="#how-should-i-write-my-code-to-utilize-these-speedups" title="Link to this heading">¶</a></h4>

  1570. <p>Write Pythonic code that follows common best practices;

  1571. you don’t have to change your code.

  1572. The Faster CPython project optimizes for common code patterns we observe.</p>

  1573. </section>

  1574. <section id="will-cpython-3-11-use-more-memory">

  1575. <span id="faster-cpython-faq-memory"></span><h4>Will CPython 3.11 use more memory?<a class="headerlink" href="#will-cpython-3-11-use-more-memory" title="Link to this heading">¶</a></h4>

  1576. <p>Maybe not; we don’t expect memory use to exceed 20% higher than 3.10.

  1577. This is offset by memory optimizations for frame objects and object

  1578. dictionaries as mentioned above.</p>

  1579. </section>

  1580. <section id="i-don-t-see-any-speedups-in-my-workload-why">

  1581. <span id="faster-cpython-ymmv"></span><h4>I don’t see any speedups in my workload. Why?<a class="headerlink" href="#i-don-t-see-any-speedups-in-my-workload-why" title="Link to this heading">¶</a></h4>

  1582. <p>Certain code won’t have noticeable benefits. If your code spends most of

  1583. its time on I/O operations, or already does most of its

  1584. computation in a C extension library like NumPy, there won’t be significant

  1585. speedups. This project currently benefits pure-Python workloads the most.</p>

  1586. <p>Furthermore, the pyperformance figures are a geometric mean. Even within the

  1587. pyperformance benchmarks, certain benchmarks have slowed down slightly, while

  1588. others have sped up by nearly 2x!</p>

  1589. </section>

  1590. <section id="is-there-a-jit-compiler">

  1591. <span id="faster-cpython-jit"></span><h4>Is there a JIT compiler?<a class="headerlink" href="#is-there-a-jit-compiler" title="Link to this heading">¶</a></h4>

  1592. <p>No. We’re still exploring other optimizations.</p>

  1593. </section>

  1594. </section>

  1595. <section id="about">

  1596. <span id="whatsnew311-faster-cpython-about"></span><h3>About<a class="headerlink" href="#about" title="Link to this heading">¶</a></h3>

  1597. <p>Faster CPython explores optimizations for <a class="reference internal" href="../glossary.html#term-CPython"><span class="xref std std-term">CPython</span></a>. The main team is

  1598. funded by Microsoft to work on this full-time. Pablo Galindo Salgado is also

  1599. funded by Bloomberg LP to work on the project part-time. Finally, many

  1600. contributors are volunteers from the community.</p>

  1601. </section>

  1602. </section>

  1603. <section id="cpython-bytecode-changes">

  1604. <span id="whatsnew311-bytecode-changes"></span><h2>CPython bytecode changes<a class="headerlink" href="#cpython-bytecode-changes" title="Link to this heading">¶</a></h2>

  1605. <p>The bytecode now contains inline cache entries,

  1606. which take the form of the newly-added <a class="reference internal" href="../library/dis.html#opcode-CACHE"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CACHE</span></code></a> instructions.

  1607. Many opcodes expect to be followed by an exact number of caches,

  1608. and instruct the interpreter to skip over them at runtime.

  1609. Populated caches can look like arbitrary instructions,

  1610. so great care should be taken when reading or modifying

  1611. raw, adaptive bytecode containing quickened data.</p>

  1612. <section id="new-opcodes">

  1613. <span id="whatsnew311-added-opcodes"></span><h3>New opcodes<a class="headerlink" href="#new-opcodes" title="Link to this heading">¶</a></h3>

  1614. <ul class="simple">

  1615. <li><p><code class="xref std std-opcode docutils literal notranslate"><span class="pre">ASYNC_GEN_WRAP</span></code>, <a class="reference internal" href="../library/dis.html#opcode-RETURN_GENERATOR"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">RETURN_GENERATOR</span></code></a> and <a class="reference internal" href="../library/dis.html#opcode-SEND"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">SEND</span></code></a>,

  1616. used in generators and co-routines.</p></li>

  1617. <li><p><a class="reference internal" href="../library/dis.html#opcode-COPY_FREE_VARS"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">COPY_FREE_VARS</span></code></a>,

  1618. which avoids needing special caller-side code for closures.</p></li>

  1619. <li><p><a class="reference internal" href="../library/dis.html#opcode-JUMP_BACKWARD_NO_INTERRUPT"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">JUMP_BACKWARD_NO_INTERRUPT</span></code></a>,

  1620. for use in certain loops where handling interrupts is undesirable.</p></li>

  1621. <li><p><a class="reference internal" href="../library/dis.html#opcode-MAKE_CELL"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">MAKE_CELL</span></code></a>, to create <a class="reference internal" href="../c-api/cell.html#cell-objects"><span class="std std-ref">Cell Objects</span></a>.</p></li>

  1622. <li><p><a class="reference internal" href="../library/dis.html#opcode-CHECK_EG_MATCH"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CHECK_EG_MATCH</span></code></a>  and  <code class="xref std std-opcode docutils literal notranslate"><span class="pre">PREP_RERAISE_STAR</span></code>,

  1623. to handle the <a class="reference internal" href="#whatsnew311-pep654"><span class="std std-ref">new exception groups and except*</span></a>

  1624. added in <span class="target" id="index-30"></span><a class="pep reference external" href="https://peps.python.org/pep-0654/"><strong>PEP 654</strong></a>.</p></li>

  1625. <li><p><a class="reference internal" href="../library/dis.html#opcode-PUSH_EXC_INFO"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">PUSH_EXC_INFO</span></code></a>, for use in exception handlers.</p></li>

  1626. <li><p><a class="reference internal" href="../library/dis.html#opcode-RESUME"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">RESUME</span></code></a>, a no-op,

  1627. for internal tracing, debugging and optimization checks.</p></li>

  1628. </ul>

  1629. </section>

  1630. <section id="replaced-opcodes">

  1631. <span id="whatsnew311-replaced-opcodes"></span><h3>Replaced opcodes<a class="headerlink" href="#replaced-opcodes" title="Link to this heading">¶</a></h3>

  1632. <table class="docutils align-default">

  1633. <thead>

  1634. <tr class="row-odd"><th class="head"><p>Replaced Opcode(s)</p></th>

  1635. <th class="head"><p>New Opcode(s)</p></th>

  1636. <th class="head"><p>Notes</p></th>

  1637. </tr>

  1638. </thead>

  1639. <tbody>

  1640. <tr class="row-even"><td><div class="line-block">

  1641. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">BINARY_*</span></code></div>

  1642. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">INPLACE_*</span></code></div>

  1643. </div>

  1644. </td>

  1645. <td><p><a class="reference internal" href="../library/dis.html#opcode-BINARY_OP"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">BINARY_OP</span></code></a></p></td>

  1646. <td><p>Replaced all numeric binary/in-place

  1647. opcodes with a single opcode</p></td>

  1648. </tr>

  1649. <tr class="row-odd"><td><div class="line-block">

  1650. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CALL_FUNCTION</span></code></div>

  1651. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CALL_FUNCTION_KW</span></code></div>

  1652. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CALL_METHOD</span></code></div>

  1653. </div>

  1654. </td>

  1655. <td><div class="line-block">

  1656. <div class="line"><a class="reference internal" href="../library/dis.html#opcode-CALL"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CALL</span></code></a></div>

  1657. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">KW_NAMES</span></code></div>

  1658. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">PRECALL</span></code></div>

  1659. <div class="line"><a class="reference internal" href="../library/dis.html#opcode-PUSH_NULL"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">PUSH_NULL</span></code></a></div>

  1660. </div>

  1661. </td>

  1662. <td><p>Decouples argument shifting for methods

  1663. from handling of keyword arguments;

  1664. allows better specialization of calls</p></td>

  1665. </tr>

  1666. <tr class="row-even"><td><div class="line-block">

  1667. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">DUP_TOP</span></code></div>

  1668. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">DUP_TOP_TWO</span></code></div>

  1669. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">ROT_TWO</span></code></div>

  1670. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">ROT_THREE</span></code></div>

  1671. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">ROT_FOUR</span></code></div>

  1672. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">ROT_N</span></code></div>

  1673. </div>

  1674. </td>

  1675. <td><div class="line-block">

  1676. <div class="line"><a class="reference internal" href="../library/dis.html#opcode-COPY"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">COPY</span></code></a></div>

  1677. <div class="line"><a class="reference internal" href="../library/dis.html#opcode-SWAP"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">SWAP</span></code></a></div>

  1678. </div>

  1679. </td>

  1680. <td><p>Stack manipulation instructions</p></td>

  1681. </tr>

  1682. <tr class="row-odd"><td><div class="line-block">

  1683. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">JUMP_IF_NOT_EXC_MATCH</span></code></div>

  1684. </div>

  1685. </td>

  1686. <td><div class="line-block">

  1687. <div class="line"><a class="reference internal" href="../library/dis.html#opcode-CHECK_EXC_MATCH"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">CHECK_EXC_MATCH</span></code></a></div>

  1688. </div>

  1689. </td>

  1690. <td><p>Now performs check but doesn’t jump</p></td>

  1691. </tr>

  1692. <tr class="row-even"><td><div class="line-block">

  1693. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">JUMP_ABSOLUTE</span></code></div>

  1694. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">POP_JUMP_IF_FALSE</span></code></div>

  1695. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">POP_JUMP_IF_TRUE</span></code></div>

  1696. </div>

  1697. </td>

  1698. <td><div class="line-block">

  1699. <div class="line"><a class="reference internal" href="../library/dis.html#opcode-JUMP_BACKWARD"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">JUMP_BACKWARD</span></code></a></div>

  1700. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">POP_JUMP_BACKWARD_IF_*</span></code></div>

  1701. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">POP_JUMP_FORWARD_IF_*</span></code></div>

  1702. </div>

  1703. </td>

  1704. <td><p>See <a class="footnote-reference brackets" href="#bytecode-jump" id="id4" role="doc-noteref"><span class="fn-bracket">[</span>3<span class="fn-bracket">]</span></a>;

  1705. <code class="docutils literal notranslate"><span class="pre">TRUE</span></code>, <code class="docutils literal notranslate"><span class="pre">FALSE</span></code>,

  1706. <code class="docutils literal notranslate"><span class="pre">NONE</span></code> and <code class="docutils literal notranslate"><span class="pre">NOT_NONE</span></code> variants

  1707. for each direction</p></td>

  1708. </tr>

  1709. <tr class="row-odd"><td><div class="line-block">

  1710. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">SETUP_WITH</span></code></div>

  1711. <div class="line"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">SETUP_ASYNC_WITH</span></code></div>

  1712. </div>

  1713. </td>

  1714. <td><p><a class="reference internal" href="../library/dis.html#opcode-BEFORE_WITH"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">BEFORE_WITH</span></code></a></p></td>

  1715. <td><p><a class="reference internal" href="../reference/compound_stmts.html#with"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">with</span></code></a> block setup</p></td>

  1716. </tr>

  1717. </tbody>

  1718. </table>

  1719. <aside class="footnote-list brackets">

  1720. <aside class="footnote brackets" id="bytecode-jump" role="doc-footnote">

  1721. <span class="label"><span class="fn-bracket">[</span><a role="doc-backlink" href="#id4">3</a><span class="fn-bracket">]</span></span>

  1722. <p>All jump opcodes are now relative, including the

  1723. existing <code class="xref std std-opcode docutils literal notranslate"><span class="pre">JUMP_IF_TRUE_OR_POP</span></code> and <code class="xref std std-opcode docutils literal notranslate"><span class="pre">JUMP_IF_FALSE_OR_POP</span></code>.

  1724. The argument is now an offset from the current instruction

  1725. rather than an absolute location.</p>

  1726. </aside>

  1727. </aside>

  1728. </section>

  1729. <section id="changed-removed-opcodes">

  1730. <span id="whatsnew311-changed-removed-opcodes"></span><span id="whatsnew311-removed-opcodes"></span><span id="whatsnew311-changed-opcodes"></span><h3>Changed/removed opcodes<a class="headerlink" href="#changed-removed-opcodes" title="Link to this heading">¶</a></h3>

  1731. <ul class="simple">

  1732. <li><p>Changed <a class="reference internal" href="../library/dis.html#opcode-MATCH_CLASS"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">MATCH_CLASS</span></code></a> and <a class="reference internal" href="../library/dis.html#opcode-MATCH_KEYS"><code class="xref std std-opcode docutils literal notranslate"><span class="pre">MATCH_KEYS</span></code></a>

  1733. to no longer push an additional boolean value to indicate success/failure.

  1734. Instead, <code class="docutils literal notranslate"><span class="pre">None</span></code> is pushed on failure

  1735. in place of the tuple of extracted values.</p></li>

  1736. <li><p>Changed opcodes that work with exceptions to reflect them

  1737. now being represented as one item on the stack instead of three

  1738. (see <a class="reference external" href="https://github.com/python/cpython/issues/89874">gh-89874</a>).</p></li>

  1739. <li><p>Removed <code class="xref std std-opcode docutils literal notranslate"><span class="pre">COPY_DICT_WITHOUT_KEYS</span></code>, <code class="xref std std-opcode docutils literal notranslate"><span class="pre">GEN_START</span></code>,

  1740. <code class="xref std std-opcode docutils literal notranslate"><span class="pre">POP_BLOCK</span></code>, <code class="xref std std-opcode docutils literal notranslate"><span class="pre">SETUP_FINALLY</span></code> and <code class="xref std std-opcode docutils literal notranslate"><span class="pre">YIELD_FROM</span></code>.</p></li>

  1741. </ul>

  1742. </section>

  1743. </section>

  1744. <section id="deprecated">

  1745. <span id="whatsnew311-python-api-deprecated"></span><span id="whatsnew311-deprecated"></span><h2>Deprecated<a class="headerlink" href="#deprecated" title="Link to this heading">¶</a></h2>

  1746. <p>This section lists Python APIs that have been deprecated in Python 3.11.</p>

  1747. <p>Deprecated C APIs are <a class="reference internal" href="#whatsnew311-c-api-deprecated"><span class="std std-ref">listed separately</span></a>.</p>

  1748. <section id="language-builtins">

  1749. <span id="whatsnew311-deprecated-builtins"></span><span id="whatsnew311-deprecated-language"></span><h3>Language/Builtins<a class="headerlink" href="#language-builtins" title="Link to this heading">¶</a></h3>

  1750. <ul class="simple">

  1751. <li><p>Chaining <a class="reference internal" href="../library/functions.html#classmethod" title="classmethod"><code class="xref py py-class docutils literal notranslate"><span class="pre">classmethod</span></code></a> descriptors (introduced in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=19072">bpo-19072</a>)

  1752. is now deprecated.  It can no longer be used to wrap other descriptors

  1753. such as <a class="reference internal" href="../library/functions.html#property" title="property"><code class="xref py py-class docutils literal notranslate"><span class="pre">property</span></code></a>.  The core design of this feature was flawed

  1754. and caused a number of downstream problems.  To “pass-through” a

  1755. <a class="reference internal" href="../library/functions.html#classmethod" title="classmethod"><code class="xref py py-class docutils literal notranslate"><span class="pre">classmethod</span></code></a>, consider using the <code class="xref py py-attr docutils literal notranslate"><span class="pre">__wrapped__</span></code> attribute

  1756. that was added in Python 3.10.

  1757. (Contributed by Raymond Hettinger in <a class="reference external" href="https://github.com/python/cpython/issues/89519">gh-89519</a>.)</p></li>

  1758. <li><p>Octal escapes in string and bytes literals with values larger than <code class="docutils literal notranslate"><span class="pre">0o377</span></code>

  1759. (255 in decimal) now produce a <a class="reference internal" href="../library/exceptions.html#DeprecationWarning" title="DeprecationWarning"><code class="xref py py-exc docutils literal notranslate"><span class="pre">DeprecationWarning</span></code></a>.

  1760. In a future Python version, they will raise a <a class="reference internal" href="../library/exceptions.html#SyntaxWarning" title="SyntaxWarning"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SyntaxWarning</span></code></a> and

  1761. eventually a <a class="reference internal" href="../library/exceptions.html#SyntaxError" title="SyntaxError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">SyntaxError</span></code></a>.

  1762. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://github.com/python/cpython/issues/81548">gh-81548</a>.)</p></li>

  1763. <li><p>The delegation of <a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-func docutils literal notranslate"><span class="pre">int()</span></code></a> to <a class="reference internal" href="../reference/datamodel.html#object.__trunc__" title="object.__trunc__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__trunc__()</span></code></a> is now deprecated.

  1764. Calling <code class="docutils literal notranslate"><span class="pre">int(a)</span></code> when <code class="docutils literal notranslate"><span class="pre">type(a)</span></code> implements <code class="xref py py-meth docutils literal notranslate"><span class="pre">__trunc__()</span></code> but not

  1765. <a class="reference internal" href="../reference/datamodel.html#object.__int__" title="object.__int__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__int__()</span></code></a> or <a class="reference internal" href="../reference/datamodel.html#object.__index__" title="object.__index__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__index__()</span></code></a> now raises

  1766. a <a class="reference internal" href="../library/exceptions.html#DeprecationWarning" title="DeprecationWarning"><code class="xref py py-exc docutils literal notranslate"><span class="pre">DeprecationWarning</span></code></a>.

  1767. (Contributed by Zackery Spytz in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44977">bpo-44977</a>.)</p></li>

  1768. </ul>

  1769. </section>

  1770. <section id="modules">

  1771. <span id="whatsnew311-deprecated-modules"></span><h3>Modules<a class="headerlink" href="#modules" title="Link to this heading">¶</a></h3>

  1772. <ul id="whatsnew311-pep594">

  1773. <li><p><span class="target" id="index-31"></span><a class="pep reference external" href="https://peps.python.org/pep-0594/"><strong>PEP 594</strong></a> led to the deprecations of the following modules

  1774. slated for removal in Python 3.13:</p>

  1775. <table class="docutils align-default">

  1776. <tbody>

  1777. <tr class="row-odd"><td><p><a class="reference internal" href="../library/aifc.html#module-aifc" title="aifc: Read and write audio files in AIFF or AIFC format. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">aifc</span></code></a></p></td>

  1778. <td><p><a class="reference internal" href="../library/chunk.html#module-chunk" title="chunk: Module to read IFF chunks. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">chunk</span></code></a></p></td>

  1779. <td><p><a class="reference internal" href="../library/msilib.html#module-msilib" title="msilib: Creation of Microsoft Installer files, and CAB files. (deprecated) (Windows)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">msilib</span></code></a></p></td>

  1780. <td><p><a class="reference internal" href="../library/pipes.html#module-pipes" title="pipes: A Python interface to Unix shell pipelines. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">pipes</span></code></a></p></td>

  1781. <td><p><a class="reference internal" href="../library/telnetlib.html#module-telnetlib" title="telnetlib: Telnet client class. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">telnetlib</span></code></a></p></td>

  1782. </tr>

  1783. <tr class="row-even"><td><p><a class="reference internal" href="../library/audioop.html#module-audioop" title="audioop: Manipulate raw audio data. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">audioop</span></code></a></p></td>

  1784. <td><p><a class="reference internal" href="../library/crypt.html#module-crypt" title="crypt: The crypt() function used to check Unix passwords. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">crypt</span></code></a></p></td>

  1785. <td><p><a class="reference internal" href="../library/nis.html#module-nis" title="nis: Interface to Sun's NIS (Yellow Pages) library. (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">nis</span></code></a></p></td>

  1786. <td><p><a class="reference internal" href="../library/sndhdr.html#module-sndhdr" title="sndhdr: Determine type of a sound file. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sndhdr</span></code></a></p></td>

  1787. <td><p><a class="reference internal" href="../library/uu.html#module-uu" title="uu: Encode and decode files in uuencode format. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">uu</span></code></a></p></td>

  1788. </tr>

  1789. <tr class="row-odd"><td><p><a class="reference internal" href="../library/cgi.html#module-cgi" title="cgi: Helpers for running Python scripts via the Common Gateway Interface. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">cgi</span></code></a></p></td>

  1790. <td><p><a class="reference internal" href="../library/imghdr.html#module-imghdr" title="imghdr: Determine the type of image contained in a file or byte stream. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">imghdr</span></code></a></p></td>

  1791. <td><p><a class="reference internal" href="../library/nntplib.html#module-nntplib" title="nntplib: NNTP protocol client (requires sockets). (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">nntplib</span></code></a></p></td>

  1792. <td><p><a class="reference internal" href="../library/spwd.html#module-spwd" title="spwd: The shadow password database (getspnam() and friends). (deprecated) (Unix)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">spwd</span></code></a></p></td>

  1793. <td><p><a class="reference internal" href="../library/xdrlib.html#module-xdrlib" title="xdrlib: Encoders and decoders for the External Data Representation (XDR). (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">xdrlib</span></code></a></p></td>

  1794. </tr>

  1795. <tr class="row-even"><td><p><a class="reference internal" href="../library/cgitb.html#module-cgitb" title="cgitb: Configurable traceback handler for CGI scripts. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">cgitb</span></code></a></p></td>

  1796. <td><p><a class="reference internal" href="../library/mailcap.html#module-mailcap" title="mailcap: Mailcap file handling. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">mailcap</span></code></a></p></td>

  1797. <td><p><a class="reference internal" href="../library/ossaudiodev.html#module-ossaudiodev" title="ossaudiodev: Access to OSS-compatible audio devices. (deprecated) (Linux, FreeBSD)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">ossaudiodev</span></code></a></p></td>

  1798. <td><p><a class="reference internal" href="../library/sunau.html#module-sunau" title="sunau: Provide an interface to the Sun AU sound format. (deprecated)"><code class="xref py py-mod docutils literal notranslate"><span class="pre">sunau</span></code></a></p></td>

  1799. <td></td>

  1800. </tr>

  1801. </tbody>

  1802. </table>

  1803. <p>(Contributed by Brett Cannon in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47061">bpo-47061</a> and Victor Stinner in

  1804. <a class="reference external" href="https://github.com/python/cpython/issues/68966">gh-68966</a>.)</p>

  1805. </li>

  1806. <li><p>The <code class="xref py py-mod docutils literal notranslate"><span class="pre">asynchat</span></code>, <code class="xref py py-mod docutils literal notranslate"><span class="pre">asyncore</span></code> and  <code class="xref py py-mod docutils literal notranslate"><span class="pre">smtpd</span></code> modules have been

  1807. deprecated since at least Python 3.6. Their documentation and deprecation

  1808. warnings have now been updated to note they will be removed in Python 3.12.

  1809. (Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47022">bpo-47022</a>.)</p></li>

  1810. <li><p>The <a class="reference internal" href="../library/2to3.html#module-lib2to3" title="lib2to3: The 2to3 library"><code class="xref py py-mod docutils literal notranslate"><span class="pre">lib2to3</span></code></a> package and <a class="reference internal" href="../library/2to3.html#to3-reference"><span class="std std-ref">2to3</span></a> tool

  1811. are now deprecated and may not be able to parse Python 3.10 or newer.

  1812. See <span class="target" id="index-32"></span><a class="pep reference external" href="https://peps.python.org/pep-0617/"><strong>PEP 617</strong></a>, introducing the new PEG parser, for details.

  1813. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40360">bpo-40360</a>.)</p></li>

  1814. <li><p>Undocumented modules <code class="xref py py-mod docutils literal notranslate"><span class="pre">sre_compile</span></code>, <code class="xref py py-mod docutils literal notranslate"><span class="pre">sre_constants</span></code>

  1815. and <code class="xref py py-mod docutils literal notranslate"><span class="pre">sre_parse</span></code> are now deprecated.

  1816. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47152">bpo-47152</a>.)</p></li>

  1817. </ul>

  1818. </section>

  1819. <section id="standard-library">

  1820. <span id="whatsnew311-deprecated-stdlib"></span><h3>Standard Library<a class="headerlink" href="#standard-library" title="Link to this heading">¶</a></h3>

  1821. <ul>

  1822. <li><p>The following have been deprecated in <a class="reference internal" href="../library/configparser.html#module-configparser" title="configparser: Configuration file parser."><code class="xref py py-mod docutils literal notranslate"><span class="pre">configparser</span></code></a> since Python 3.2.

  1823. Their deprecation warnings have now been updated to note they will be removed

  1824. in Python 3.12:</p>

  1825. <ul class="simple">

  1826. <li><p>the <code class="xref py py-class docutils literal notranslate"><span class="pre">configparser.SafeConfigParser</span></code> class</p></li>

  1827. <li><p>the <code class="xref py py-attr docutils literal notranslate"><span class="pre">configparser.ParsingError.filename</span></code> property</p></li>

  1828. <li><p>the <code class="xref py py-meth docutils literal notranslate"><span class="pre">configparser.RawConfigParser.readfp()</span></code> method</p></li>

  1829. </ul>

  1830. <p>(Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45173">bpo-45173</a>.)</p>

  1831. </li>

  1832. <li><p><code class="xref py py-class docutils literal notranslate"><span class="pre">configparser.LegacyInterpolation</span></code> has been deprecated in the docstring

  1833. since Python 3.2, and is not listed in the <a class="reference internal" href="../library/configparser.html#module-configparser" title="configparser: Configuration file parser."><code class="xref py py-mod docutils literal notranslate"><span class="pre">configparser</span></code></a> documentation.

  1834. It now emits a <a class="reference internal" href="../library/exceptions.html#DeprecationWarning" title="DeprecationWarning"><code class="xref py py-exc docutils literal notranslate"><span class="pre">DeprecationWarning</span></code></a> and will be removed

  1835. in Python 3.13. Use <a class="reference internal" href="../library/configparser.html#configparser.BasicInterpolation" title="configparser.BasicInterpolation"><code class="xref py py-class docutils literal notranslate"><span class="pre">configparser.BasicInterpolation</span></code></a> or

  1836. <a class="reference internal" href="../library/configparser.html#configparser.ExtendedInterpolation" title="configparser.ExtendedInterpolation"><code class="xref py py-class docutils literal notranslate"><span class="pre">configparser.ExtendedInterpolation</span></code></a> instead.

  1837. (Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46607">bpo-46607</a>.)</p></li>

  1838. <li><p>The older set of <a class="reference internal" href="../library/importlib.resources.html#module-importlib.resources" title="importlib.resources: Package resource reading, opening, and access"><code class="xref py py-mod docutils literal notranslate"><span class="pre">importlib.resources</span></code></a> functions were deprecated

  1839. in favor of the replacements added in Python 3.9

  1840. and will be removed in a future Python version,

  1841. due to not supporting resources located within package subdirectories:</p>

  1842. <ul class="simple">

  1843. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.contents" title="importlib.resources.contents"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.contents()</span></code></a></p></li>

  1844. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.is_resource" title="importlib.resources.is_resource"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.is_resource()</span></code></a></p></li>

  1845. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.open_binary" title="importlib.resources.open_binary"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.open_binary()</span></code></a></p></li>

  1846. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.open_text" title="importlib.resources.open_text"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.open_text()</span></code></a></p></li>

  1847. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.read_binary" title="importlib.resources.read_binary"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.read_binary()</span></code></a></p></li>

  1848. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.read_text" title="importlib.resources.read_text"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.read_text()</span></code></a></p></li>

  1849. <li><p><a class="reference internal" href="../library/importlib.resources.html#importlib.resources.path" title="importlib.resources.path"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.resources.path()</span></code></a></p></li>

  1850. </ul>

  1851. </li>

  1852. <li><p>The <a class="reference internal" href="../library/locale.html#locale.getdefaultlocale" title="locale.getdefaultlocale"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.getdefaultlocale()</span></code></a> function is deprecated and will be

  1853. removed in Python 3.15. Use <a class="reference internal" href="../library/locale.html#locale.setlocale" title="locale.setlocale"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.setlocale()</span></code></a>,

  1854. <a class="reference internal" href="../library/locale.html#locale.getpreferredencoding" title="locale.getpreferredencoding"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.getpreferredencoding(False)</span></code></a> and

  1855. <a class="reference internal" href="../library/locale.html#locale.getlocale" title="locale.getlocale"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.getlocale()</span></code></a> functions instead.

  1856. (Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/90817">gh-90817</a>.)</p></li>

  1857. <li><p>The <a class="reference internal" href="../library/locale.html#locale.resetlocale" title="locale.resetlocale"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.resetlocale()</span></code></a> function is deprecated and will be

  1858. removed in Python 3.13. Use <code class="docutils literal notranslate"><span class="pre">locale.setlocale(locale.LC_ALL,</span> <span class="pre">&quot;&quot;)</span></code> instead.

  1859. (Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/90817">gh-90817</a>.)</p></li>

  1860. <li><p>Stricter rules will now be applied for numerical group references

  1861. and group names in <a class="reference internal" href="../library/re.html#re-syntax"><span class="std std-ref">regular expressions</span></a>.

  1862. Only sequences of ASCII digits will now be accepted as a numerical reference,

  1863. and the group name in <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytes</span></code></a> patterns and replacement strings

  1864. can only contain ASCII letters, digits and underscores.

  1865. For now, a deprecation warning is raised for syntax violating these rules.

  1866. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://github.com/python/cpython/issues/91760">gh-91760</a>.)</p></li>

  1867. <li><p>In the <a class="reference internal" href="../library/re.html#module-re" title="re: Regular expression operations."><code class="xref py py-mod docutils literal notranslate"><span class="pre">re</span></code></a> module, the <code class="xref py py-func docutils literal notranslate"><span class="pre">re.template()</span></code> function

  1868. and the corresponding <code class="xref py py-const docutils literal notranslate"><span class="pre">re.TEMPLATE</span></code> and <code class="xref py py-const docutils literal notranslate"><span class="pre">re.T</span></code> flags

  1869. are deprecated, as they were undocumented and lacked an obvious purpose.

  1870. They will be removed in Python 3.13.

  1871. (Contributed by Serhiy Storchaka and Miro Hrončok in <a class="reference external" href="https://github.com/python/cpython/issues/92728">gh-92728</a>.)</p></li>

  1872. <li><p><a class="reference internal" href="../library/turtle.html#turtle.settiltangle" title="turtle.settiltangle"><code class="xref py py-func docutils literal notranslate"><span class="pre">turtle.settiltangle()</span></code></a> has been deprecated since Python 3.1;

  1873. it now emits a deprecation warning and will be removed in Python 3.13. Use

  1874. <a class="reference internal" href="../library/turtle.html#turtle.tiltangle" title="turtle.tiltangle"><code class="xref py py-func docutils literal notranslate"><span class="pre">turtle.tiltangle()</span></code></a> instead (it was earlier incorrectly marked

  1875. as deprecated, and its docstring is now corrected).

  1876. (Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45837">bpo-45837</a>.)</p></li>

  1877. <li><p><a class="reference internal" href="../library/typing.html#typing.Text" title="typing.Text"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.Text</span></code></a>, which exists solely to provide compatibility support

  1878. between Python 2 and Python 3 code, is now deprecated. Its removal is

  1879. currently unplanned, but users are encouraged to use <a class="reference internal" href="../library/stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a> instead

  1880. wherever possible.

  1881. (Contributed by Alex Waygood in <a class="reference external" href="https://github.com/python/cpython/issues/92332">gh-92332</a>.)</p></li>

  1882. <li><p>The keyword argument syntax for constructing <a class="reference internal" href="../library/typing.html#typing.TypedDict" title="typing.TypedDict"><code class="xref py py-data docutils literal notranslate"><span class="pre">typing.TypedDict</span></code></a> types

  1883. is now deprecated. Support will be removed in Python 3.13. (Contributed by

  1884. Jingchen Ye in <a class="reference external" href="https://github.com/python/cpython/issues/90224">gh-90224</a>.)</p></li>

  1885. <li><p><code class="xref py py-class docutils literal notranslate"><span class="pre">webbrowser.MacOSX</span></code> is deprecated and will be removed in Python 3.13.

  1886. It is untested, undocumented, and not used by <a class="reference internal" href="../library/webbrowser.html#module-webbrowser" title="webbrowser: Easy-to-use controller for web browsers."><code class="xref py py-mod docutils literal notranslate"><span class="pre">webbrowser</span></code></a> itself.

  1887. (Contributed by Donghee Na in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=42255">bpo-42255</a>.)</p></li>

  1888. <li><p>The behavior of returning a value from a <a class="reference internal" href="../library/unittest.html#unittest.TestCase" title="unittest.TestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestCase</span></code></a> and

  1889. <a class="reference internal" href="../library/unittest.html#unittest.IsolatedAsyncioTestCase" title="unittest.IsolatedAsyncioTestCase"><code class="xref py py-class docutils literal notranslate"><span class="pre">IsolatedAsyncioTestCase</span></code></a> test methods (other than the

  1890. default <code class="docutils literal notranslate"><span class="pre">None</span></code> value) is now deprecated.</p></li>

  1891. <li><p>Deprecated the following not-formally-documented <a class="reference internal" href="../library/unittest.html#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> functions,

  1892. scheduled for removal in Python 3.13:</p>

  1893. <ul class="simple">

  1894. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.findTestCases()</span></code></p></li>

  1895. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.makeSuite()</span></code></p></li>

  1896. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">unittest.getTestCaseNames()</span></code></p></li>

  1897. </ul>

  1898. <p>Use <a class="reference internal" href="../library/unittest.html#unittest.TestLoader" title="unittest.TestLoader"><code class="xref py py-class docutils literal notranslate"><span class="pre">TestLoader</span></code></a> methods instead:</p>

  1899. <ul class="simple">

  1900. <li><p><a class="reference internal" href="../library/unittest.html#unittest.TestLoader.loadTestsFromModule" title="unittest.TestLoader.loadTestsFromModule"><code class="xref py py-meth docutils literal notranslate"><span class="pre">unittest.TestLoader.loadTestsFromModule()</span></code></a></p></li>

  1901. <li><p><a class="reference internal" href="../library/unittest.html#unittest.TestLoader.loadTestsFromTestCase" title="unittest.TestLoader.loadTestsFromTestCase"><code class="xref py py-meth docutils literal notranslate"><span class="pre">unittest.TestLoader.loadTestsFromTestCase()</span></code></a></p></li>

  1902. <li><p><a class="reference internal" href="../library/unittest.html#unittest.TestLoader.getTestCaseNames" title="unittest.TestLoader.getTestCaseNames"><code class="xref py py-meth docutils literal notranslate"><span class="pre">unittest.TestLoader.getTestCaseNames()</span></code></a></p></li>

  1903. </ul>

  1904. <p>(Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=5846">bpo-5846</a>.)</p>

  1905. </li>

  1906. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">unittest.TestProgram.usageExit()</span></code> is marked deprecated, to be removed

  1907. in 3.13.

  1908. (Contributed by Carlos Damázio in <a class="reference external" href="https://github.com/python/cpython/issues/67048">gh-67048</a>.)</p></li>

  1909. </ul>

  1910. </section>

  1911. </section>

  1912. <section id="pending-removal-in-python-3-12">

  1913. <span id="whatsnew311-python-api-pending-removal"></span><span id="whatsnew311-pending-removal"></span><h2>Pending Removal in Python 3.12<a class="headerlink" href="#pending-removal-in-python-3-12" title="Link to this heading">¶</a></h2>

  1914. <p>The following Python APIs have been deprecated in earlier Python releases,

  1915. and will be removed in Python 3.12.</p>

  1916. <p>C APIs pending removal are

  1917. <a class="reference internal" href="#whatsnew311-c-api-pending-removal"><span class="std std-ref">listed separately</span></a>.</p>

  1918. <ul>

  1919. <li><p>The <code class="xref py py-mod docutils literal notranslate"><span class="pre">asynchat</span></code> module</p></li>

  1920. <li><p>The <code class="xref py py-mod docutils literal notranslate"><span class="pre">asyncore</span></code> module</p></li>

  1921. <li><p>The <a class="reference internal" href="3.10.html#distutils-deprecated"><span class="std std-ref">entire distutils package</span></a></p></li>

  1922. <li><p>The <code class="xref py py-mod docutils literal notranslate"><span class="pre">imp</span></code> module</p></li>

  1923. <li><p>The <a class="reference internal" href="../library/typing.html#typing.IO" title="typing.IO"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.io</span></code></a> namespace</p></li>

  1924. <li><p>The <a class="reference internal" href="../library/typing.html#typing.Pattern" title="typing.Pattern"><code class="xref py py-class docutils literal notranslate"><span class="pre">typing.re</span></code></a> namespace</p></li>

  1925. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">cgi.log()</span></code></p></li>

  1926. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.find_loader()</span></code></p></li>

  1927. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.abc.Loader.module_repr()</span></code></p></li>

  1928. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.abc.MetaPathFinder.find_module()</span></code></p></li>

  1929. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.abc.PathEntryFinder.find_loader()</span></code></p></li>

  1930. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.abc.PathEntryFinder.find_module()</span></code></p></li>

  1931. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.BuiltinImporter.find_module()</span></code></p></li>

  1932. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.BuiltinLoader.module_repr()</span></code></p></li>

  1933. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.FileFinder.find_loader()</span></code></p></li>

  1934. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.FileFinder.find_module()</span></code></p></li>

  1935. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.FrozenImporter.find_module()</span></code></p></li>

  1936. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.FrozenLoader.module_repr()</span></code></p></li>

  1937. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.PathFinder.find_module()</span></code></p></li>

  1938. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">importlib.machinery.WindowsRegistryFinder.find_module()</span></code></p></li>

  1939. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.util.module_for_loader()</span></code></p></li>

  1940. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.util.set_loader_wrapper()</span></code></p></li>

  1941. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.util.set_package_wrapper()</span></code></p></li>

  1942. <li><p><code class="xref py py-class docutils literal notranslate"><span class="pre">pkgutil.ImpImporter</span></code></p></li>

  1943. <li><p><code class="xref py py-class docutils literal notranslate"><span class="pre">pkgutil.ImpLoader</span></code></p></li>

  1944. <li><p><code class="xref py py-meth docutils literal notranslate"><span class="pre">pathlib.Path.link_to()</span></code></p></li>

  1945. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">sqlite3.enable_shared_cache()</span></code></p></li>

  1946. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">sqlite3.OptimizedUnicode()</span></code></p></li>

  1947. <li><p><code class="xref std std-envvar docutils literal notranslate"><span class="pre">PYTHONTHREADDEBUG</span></code> environment variable</p></li>

  1948. <li><p>The following deprecated aliases in <a class="reference internal" href="../library/unittest.html#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a>:</p>

  1949. <blockquote>

  1950. <div><table class="docutils align-default">

  1951. <thead>

  1952. <tr class="row-odd"><th class="head"><p>Deprecated alias</p></th>

  1953. <th class="head"><p>Method Name</p></th>

  1954. <th class="head"><p>Deprecated in</p></th>

  1955. </tr>

  1956. </thead>

  1957. <tbody>

  1958. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">failUnless</span></code></p></td>

  1959. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTrue()</span></code></a></p></td>

  1960. <td><p>3.1</p></td>

  1961. </tr>

  1962. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">failIf</span></code></p></td>

  1963. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertFalse" title="unittest.TestCase.assertFalse"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertFalse()</span></code></a></p></td>

  1964. <td><p>3.1</p></td>

  1965. </tr>

  1966. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">failUnlessEqual</span></code></p></td>

  1967. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a></p></td>

  1968. <td><p>3.1</p></td>

  1969. </tr>

  1970. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">failIfEqual</span></code></p></td>

  1971. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertNotEqual" title="unittest.TestCase.assertNotEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotEqual()</span></code></a></p></td>

  1972. <td><p>3.1</p></td>

  1973. </tr>

  1974. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">failUnlessAlmostEqual</span></code></p></td>

  1975. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertAlmostEqual()</span></code></a></p></td>

  1976. <td><p>3.1</p></td>

  1977. </tr>

  1978. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">failIfAlmostEqual</span></code></p></td>

  1979. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotAlmostEqual()</span></code></a></p></td>

  1980. <td><p>3.1</p></td>

  1981. </tr>

  1982. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">failUnlessRaises</span></code></p></td>

  1983. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertRaises" title="unittest.TestCase.assertRaises"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaises()</span></code></a></p></td>

  1984. <td><p>3.1</p></td>

  1985. </tr>

  1986. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">assert_</span></code></p></td>

  1987. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertTrue" title="unittest.TestCase.assertTrue"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertTrue()</span></code></a></p></td>

  1988. <td><p>3.2</p></td>

  1989. </tr>

  1990. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">assertEquals</span></code></p></td>

  1991. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertEqual" title="unittest.TestCase.assertEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertEqual()</span></code></a></p></td>

  1992. <td><p>3.2</p></td>

  1993. </tr>

  1994. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">assertNotEquals</span></code></p></td>

  1995. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertNotEqual" title="unittest.TestCase.assertNotEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotEqual()</span></code></a></p></td>

  1996. <td><p>3.2</p></td>

  1997. </tr>

  1998. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">assertAlmostEquals</span></code></p></td>

  1999. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertAlmostEqual" title="unittest.TestCase.assertAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertAlmostEqual()</span></code></a></p></td>

  2000. <td><p>3.2</p></td>

  2001. </tr>

  2002. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">assertNotAlmostEquals</span></code></p></td>

  2003. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertNotAlmostEqual" title="unittest.TestCase.assertNotAlmostEqual"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotAlmostEqual()</span></code></a></p></td>

  2004. <td><p>3.2</p></td>

  2005. </tr>

  2006. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">assertRegexpMatches</span></code></p></td>

  2007. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertRegex" title="unittest.TestCase.assertRegex"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRegex()</span></code></a></p></td>

  2008. <td><p>3.2</p></td>

  2009. </tr>

  2010. <tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">assertRaisesRegexp</span></code></p></td>

  2011. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertRaisesRegex" title="unittest.TestCase.assertRaisesRegex"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertRaisesRegex()</span></code></a></p></td>

  2012. <td><p>3.2</p></td>

  2013. </tr>

  2014. <tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">assertNotRegexpMatches</span></code></p></td>

  2015. <td><p><a class="reference internal" href="../library/unittest.html#unittest.TestCase.assertNotRegex" title="unittest.TestCase.assertNotRegex"><code class="xref py py-meth docutils literal notranslate"><span class="pre">assertNotRegex()</span></code></a></p></td>

  2016. <td><p>3.5</p></td>

  2017. </tr>

  2018. </tbody>

  2019. </table>

  2020. </div></blockquote>

  2021. </li>

  2022. </ul>

  2023. </section>

  2024. <section id="removed">

  2025. <span id="whatsnew311-python-api-removed"></span><span id="whatsnew311-removed"></span><h2>Removed<a class="headerlink" href="#removed" title="Link to this heading">¶</a></h2>

  2026. <p>This section lists Python APIs that have been removed in Python 3.11.</p>

  2027. <p>Removed C APIs are <a class="reference internal" href="#whatsnew311-c-api-removed"><span class="std std-ref">listed separately</span></a>.</p>

  2028. <ul>

  2029. <li><p>Removed the <code class="xref py py-func docutils literal notranslate"><span class="pre">&#64;asyncio.coroutine()</span></code> <a class="reference internal" href="../glossary.html#term-decorator"><span class="xref std std-term">decorator</span></a>

  2030. enabling legacy generator-based coroutines to be compatible with

  2031. <a class="reference internal" href="../reference/compound_stmts.html#async"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">async</span></code></a> / <a class="reference internal" href="../reference/expressions.html#await"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">await</span></code></a> code.

  2032. The function has been deprecated since Python 3.8 and the removal was

  2033. initially scheduled for Python 3.10. Use <a class="reference internal" href="../reference/compound_stmts.html#async-def"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">async</span> <span class="pre">def</span></code></a> instead.

  2034. (Contributed by Illia Volochii in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43216">bpo-43216</a>.)</p></li>

  2035. <li><p>Removed <code class="xref py py-class docutils literal notranslate"><span class="pre">asyncio.coroutines.CoroWrapper</span></code> used for wrapping legacy

  2036. generator-based coroutine objects in the debug mode.

  2037. (Contributed by Illia Volochii in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43216">bpo-43216</a>.)</p></li>

  2038. <li><p>Due to significant security concerns, the <em>reuse_address</em> parameter of

  2039. <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.loop.create_datagram_endpoint" title="asyncio.loop.create_datagram_endpoint"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.loop.create_datagram_endpoint()</span></code></a>, disabled in Python 3.9, is

  2040. now entirely removed. This is because of the behavior of the socket option

  2041. <code class="docutils literal notranslate"><span class="pre">SO_REUSEADDR</span></code> in UDP.

  2042. (Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45129">bpo-45129</a>.)</p></li>

  2043. <li><p>Removed the <code class="xref py py-mod docutils literal notranslate"><span class="pre">binhex</span></code> module, deprecated in Python 3.9.

  2044. Also removed the related, similarly-deprecated <a class="reference internal" href="../library/binascii.html#module-binascii" title="binascii: Tools for converting between binary and various ASCII-encoded binary representations."><code class="xref py py-mod docutils literal notranslate"><span class="pre">binascii</span></code></a> functions:</p>

  2045. <ul class="simple">

  2046. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">binascii.a2b_hqx()</span></code></p></li>

  2047. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">binascii.b2a_hqx()</span></code></p></li>

  2048. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">binascii.rlecode_hqx()</span></code></p></li>

  2049. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">binascii.rldecode_hqx()</span></code></p></li>

  2050. </ul>

  2051. <p>The <a class="reference internal" href="../library/binascii.html#binascii.crc_hqx" title="binascii.crc_hqx"><code class="xref py py-func docutils literal notranslate"><span class="pre">binascii.crc_hqx()</span></code></a> function remains available.</p>

  2052. <p>(Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45085">bpo-45085</a>.)</p>

  2053. </li>

  2054. <li><p>Removed the <code class="xref py py-mod docutils literal notranslate"><span class="pre">distutils</span></code> <code class="docutils literal notranslate"><span class="pre">bdist_msi</span></code> command deprecated in Python 3.9.

  2055. Use <code class="docutils literal notranslate"><span class="pre">bdist_wheel</span></code> (wheel packages) instead.

  2056. (Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45124">bpo-45124</a>.)</p></li>

  2057. <li><p>Removed the <a class="reference internal" href="../reference/datamodel.html#object.__getitem__" title="object.__getitem__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__getitem__()</span></code></a> methods of

  2058. <a class="reference internal" href="../library/xml.dom.pulldom.html#xml.dom.pulldom.DOMEventStream" title="xml.dom.pulldom.DOMEventStream"><code class="xref py py-class docutils literal notranslate"><span class="pre">xml.dom.pulldom.DOMEventStream</span></code></a>, <a class="reference internal" href="../library/wsgiref.html#wsgiref.util.FileWrapper" title="wsgiref.util.FileWrapper"><code class="xref py py-class docutils literal notranslate"><span class="pre">wsgiref.util.FileWrapper</span></code></a>

  2059. and <a class="reference internal" href="../library/fileinput.html#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">fileinput.FileInput</span></code></a>, deprecated since Python 3.9.

  2060. (Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45132">bpo-45132</a>.)</p></li>

  2061. <li><p>Removed the deprecated <a class="reference internal" href="../library/gettext.html#module-gettext" title="gettext: Multilingual internationalization services."><code class="xref py py-mod docutils literal notranslate"><span class="pre">gettext</span></code></a> functions

  2062. <code class="xref py py-func docutils literal notranslate"><span class="pre">lgettext()</span></code>, <code class="xref py py-func docutils literal notranslate"><span class="pre">ldgettext()</span></code>,

  2063. <code class="xref py py-func docutils literal notranslate"><span class="pre">lngettext()</span></code> and <code class="xref py py-func docutils literal notranslate"><span class="pre">ldngettext()</span></code>.

  2064. Also removed the <code class="xref py py-func docutils literal notranslate"><span class="pre">bind_textdomain_codeset()</span></code> function,

  2065. the <code class="xref py py-meth docutils literal notranslate"><span class="pre">NullTranslations.output_charset()</span></code> and

  2066. <code class="xref py py-meth docutils literal notranslate"><span class="pre">NullTranslations.set_output_charset()</span></code> methods,

  2067. and the <em>codeset</em> parameter of <code class="xref py py-func docutils literal notranslate"><span class="pre">translation()</span></code> and <code class="xref py py-func docutils literal notranslate"><span class="pre">install()</span></code>,

  2068. since they are only used for the <code class="xref py py-func docutils literal notranslate"><span class="pre">l*gettext()</span></code> functions.

  2069. (Contributed by Donghee Na and Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44235">bpo-44235</a>.)</p></li>

  2070. <li><p>Removed from the <a class="reference internal" href="../library/inspect.html#module-inspect" title="inspect: Extract information and source code from live objects."><code class="xref py py-mod docutils literal notranslate"><span class="pre">inspect</span></code></a> module:</p>

  2071. <ul class="simple">

  2072. <li><p>The <code class="xref py py-func docutils literal notranslate"><span class="pre">getargspec()</span></code> function, deprecated since Python 3.0;

  2073. use <a class="reference internal" href="../library/inspect.html#inspect.signature" title="inspect.signature"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.signature()</span></code></a> or <a class="reference internal" href="../library/inspect.html#inspect.getfullargspec" title="inspect.getfullargspec"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.getfullargspec()</span></code></a> instead.</p></li>

  2074. <li><p>The <code class="xref py py-func docutils literal notranslate"><span class="pre">formatargspec()</span></code> function, deprecated since Python 3.5;

  2075. use the <a class="reference internal" href="../library/inspect.html#inspect.signature" title="inspect.signature"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.signature()</span></code></a> function

  2076. or the <a class="reference internal" href="../library/inspect.html#inspect.Signature" title="inspect.Signature"><code class="xref py py-class docutils literal notranslate"><span class="pre">inspect.Signature</span></code></a> object directly.</p></li>

  2077. <li><p>The undocumented <code class="xref py py-meth docutils literal notranslate"><span class="pre">Signature.from_builtin()</span></code>

  2078. and <code class="xref py py-meth docutils literal notranslate"><span class="pre">Signature.from_function()</span></code> methods, deprecated since Python 3.5;

  2079. use the <a class="reference internal" href="../library/inspect.html#inspect.Signature.from_callable" title="inspect.Signature.from_callable"><code class="xref py py-meth docutils literal notranslate"><span class="pre">Signature.from_callable()</span></code></a>

  2080. method instead.</p></li>

  2081. </ul>

  2082. <p>(Contributed by Hugo van Kemenade in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45320">bpo-45320</a>.)</p>

  2083. </li>

  2084. <li><p>Removed the <a class="reference internal" href="../reference/datamodel.html#object.__class_getitem__" title="object.__class_getitem__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__class_getitem__()</span></code></a> method

  2085. from <a class="reference internal" href="../library/pathlib.html#pathlib.PurePath" title="pathlib.PurePath"><code class="xref py py-class docutils literal notranslate"><span class="pre">pathlib.PurePath</span></code></a>,

  2086. because it was not used and added by mistake in previous versions.

  2087. (Contributed by Nikita Sobolev in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46483">bpo-46483</a>.)</p></li>

  2088. <li><p>Removed the <code class="xref py py-class docutils literal notranslate"><span class="pre">MailmanProxy</span></code> class in the <code class="xref py py-mod docutils literal notranslate"><span class="pre">smtpd</span></code> module,

  2089. as it is unusable without the external <code class="xref py py-mod docutils literal notranslate"><span class="pre">mailman</span></code> package.

  2090. (Contributed by Donghee Na in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=35800">bpo-35800</a>.)</p></li>

  2091. <li><p>Removed the deprecated <code class="xref py py-meth docutils literal notranslate"><span class="pre">split()</span></code> method of <code class="xref py py-class docutils literal notranslate"><span class="pre">_tkinter.TkappType</span></code>.

  2092. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=38371">bpo-38371</a>.)</p></li>

  2093. <li><p>Removed namespace package support from <a class="reference internal" href="../library/unittest.html#module-unittest" title="unittest: Unit testing framework for Python."><code class="xref py py-mod docutils literal notranslate"><span class="pre">unittest</span></code></a> discovery.

  2094. It was introduced in Python 3.4 but has been broken since Python 3.7.

  2095. (Contributed by Inada Naoki in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=23882">bpo-23882</a>.)</p></li>

  2096. <li><p>Removed the undocumented private <code class="xref py py-meth docutils literal notranslate"><span class="pre">float.__set_format__()</span></code> method,

  2097. previously known as <code class="xref py py-meth docutils literal notranslate"><span class="pre">float.__setformat__()</span></code> in Python 3.7.

  2098. Its docstring said: “You probably don’t want to use this function.

  2099. It exists mainly to be used in Python’s test suite.”

  2100. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46852">bpo-46852</a>.)</p></li>

  2101. <li><p>The <code class="xref std std-option docutils literal notranslate"><span class="pre">--experimental-isolated-subinterpreters</span></code> configure flag

  2102. (and corresponding <code class="xref c c-macro docutils literal notranslate"><span class="pre">EXPERIMENTAL_ISOLATED_SUBINTERPRETERS</span></code> macro)

  2103. have been removed.</p></li>

  2104. <li><p><a class="reference external" href="https://pypi.org/project/pynche/">Pynche</a>

  2105. — The Pythonically Natural Color and Hue Editor — has been moved out

  2106. of <code class="docutils literal notranslate"><span class="pre">Tools/scripts</span></code> and is <a class="reference external" href="https://gitlab.com/warsaw/pynche/-/tree/main">being developed independently</a> from the Python source tree.</p></li>

  2107. </ul>

  2108. </section>

  2109. <section id="porting-to-python-3-11">

  2110. <span id="whatsnew311-python-api-porting"></span><span id="whatsnew311-porting"></span><h2>Porting to Python 3.11<a class="headerlink" href="#porting-to-python-3-11" title="Link to this heading">¶</a></h2>

  2111. <p>This section lists previously described changes and other bugfixes

  2112. in the Python API that may require changes to your Python code.</p>

  2113. <p>Porting notes for the C API are

  2114. <a class="reference internal" href="#whatsnew311-c-api-porting"><span class="std std-ref">listed separately</span></a>.</p>

  2115. <ul class="simple">

  2116. <li><p><a class="reference internal" href="../library/functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a>, <a class="reference internal" href="../library/io.html#io.open" title="io.open"><code class="xref py py-func docutils literal notranslate"><span class="pre">io.open()</span></code></a>, <a class="reference internal" href="../library/codecs.html#codecs.open" title="codecs.open"><code class="xref py py-func docutils literal notranslate"><span class="pre">codecs.open()</span></code></a> and

  2117. <a class="reference internal" href="../library/fileinput.html#fileinput.FileInput" title="fileinput.FileInput"><code class="xref py py-class docutils literal notranslate"><span class="pre">fileinput.FileInput</span></code></a> no longer accept <code class="docutils literal notranslate"><span class="pre">'U'</span></code> (“universal newline”)

  2118. in the file mode. In Python 3, “universal newline” mode is used by default

  2119. whenever a file is opened in text mode,

  2120. and the <code class="docutils literal notranslate"><span class="pre">'U'</span></code> flag has been deprecated since Python 3.3.

  2121. The <a class="reference internal" href="../library/functions.html#open-newline-parameter"><span class="std std-ref">newline parameter</span></a>

  2122. to these functions controls how universal newlines work.

  2123. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=37330">bpo-37330</a>.)</p></li>

  2124. <li><p><a class="reference internal" href="../library/ast.html#ast.AST" title="ast.AST"><code class="xref py py-class docutils literal notranslate"><span class="pre">ast.AST</span></code></a> node positions are now validated when provided to

  2125. <a class="reference internal" href="../library/functions.html#compile" title="compile"><code class="xref py py-func docutils literal notranslate"><span class="pre">compile()</span></code></a> and other related functions. If invalid positions are detected,

  2126. a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> will be raised. (Contributed by Pablo Galindo in <a class="reference external" href="https://github.com/python/cpython/issues/93351">gh-93351</a>)</p></li>

  2127. <li><p>Prohibited passing non-<a class="reference internal" href="../library/concurrent.futures.html#concurrent.futures.ThreadPoolExecutor" title="concurrent.futures.ThreadPoolExecutor"><code class="xref py py-class docutils literal notranslate"><span class="pre">concurrent.futures.ThreadPoolExecutor</span></code></a>

  2128. executors to <a class="reference internal" href="../library/asyncio-eventloop.html#asyncio.loop.set_default_executor" title="asyncio.loop.set_default_executor"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.loop.set_default_executor()</span></code></a>

  2129. following a deprecation in Python 3.8.

  2130. (Contributed by Illia Volochii in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43234">bpo-43234</a>.)</p></li>

  2131. <li><p><a class="reference internal" href="../library/calendar.html#module-calendar" title="calendar: Functions for working with calendars, including some emulation of the Unix cal program."><code class="xref py py-mod docutils literal notranslate"><span class="pre">calendar</span></code></a>: The <a class="reference internal" href="../library/calendar.html#calendar.LocaleTextCalendar" title="calendar.LocaleTextCalendar"><code class="xref py py-class docutils literal notranslate"><span class="pre">calendar.LocaleTextCalendar</span></code></a> and

  2132. <a class="reference internal" href="../library/calendar.html#calendar.LocaleHTMLCalendar" title="calendar.LocaleHTMLCalendar"><code class="xref py py-class docutils literal notranslate"><span class="pre">calendar.LocaleHTMLCalendar</span></code></a> classes now use

  2133. <a class="reference internal" href="../library/locale.html#locale.getlocale" title="locale.getlocale"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.getlocale()</span></code></a>, instead of using <a class="reference internal" href="../library/locale.html#locale.getdefaultlocale" title="locale.getdefaultlocale"><code class="xref py py-func docutils literal notranslate"><span class="pre">locale.getdefaultlocale()</span></code></a>,

  2134. if no locale is specified.

  2135. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46659">bpo-46659</a>.)</p></li>

  2136. <li><p>The <a class="reference internal" href="../library/pdb.html#module-pdb" title="pdb: The Python debugger for interactive interpreters."><code class="xref py py-mod docutils literal notranslate"><span class="pre">pdb</span></code></a> module now reads the <code class="file docutils literal notranslate"><span class="pre">.pdbrc</span></code> configuration file with

  2137. the <code class="docutils literal notranslate"><span class="pre">'UTF-8'</span></code> encoding.

  2138. (Contributed by Srinivas Reddy Thatiparthy (శ్రీనివాస్  రెడ్డి తాటిపర్తి) in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=41137">bpo-41137</a>.)</p></li>

  2139. <li><p>The <em>population</em> parameter of <a class="reference internal" href="../library/random.html#random.sample" title="random.sample"><code class="xref py py-func docutils literal notranslate"><span class="pre">random.sample()</span></code></a> must be a sequence,

  2140. and automatic conversion of <a class="reference internal" href="../library/stdtypes.html#set" title="set"><code class="xref py py-class docutils literal notranslate"><span class="pre">set</span></code></a>s to <a class="reference internal" href="../library/stdtypes.html#list" title="list"><code class="xref py py-class docutils literal notranslate"><span class="pre">list</span></code></a>s

  2141. is no longer supported. Also, if the sample size

  2142. is larger than the population size, a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> is raised.

  2143. (Contributed by Raymond Hettinger in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40465">bpo-40465</a>.)</p></li>

  2144. <li><p>The <em>random</em> optional parameter of <a class="reference internal" href="../library/random.html#random.shuffle" title="random.shuffle"><code class="xref py py-func docutils literal notranslate"><span class="pre">random.shuffle()</span></code></a> was removed.

  2145. It was previously an arbitrary random function to use for the shuffle;

  2146. now, <a class="reference internal" href="../library/random.html#random.random" title="random.random"><code class="xref py py-func docutils literal notranslate"><span class="pre">random.random()</span></code></a> (its previous default) will always be used.</p></li>

  2147. <li><p>In <a class="reference internal" href="../library/re.html#module-re" title="re: Regular expression operations."><code class="xref py py-mod docutils literal notranslate"><span class="pre">re</span></code></a> <a class="reference internal" href="../library/re.html#re-syntax"><span class="std std-ref">Regular Expression Syntax</span></a>, global inline flags (e.g. <code class="docutils literal notranslate"><span class="pre">(?i)</span></code>)

  2148. can now only be used at the start of regular expressions.

  2149. Using them elsewhere has been deprecated since Python 3.6.

  2150. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=47066">bpo-47066</a>.)</p></li>

  2151. <li><p>In the <a class="reference internal" href="../library/re.html#module-re" title="re: Regular expression operations."><code class="xref py py-mod docutils literal notranslate"><span class="pre">re</span></code></a> module, several long-standing bugs where fixed that,

  2152. in rare cases, could cause capture groups to get the wrong result.

  2153. Therefore, this could change the captured output in these cases.

  2154. (Contributed by Ma Lin in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=35859">bpo-35859</a>.)</p></li>

  2155. </ul>

  2156. </section>

  2157. <section id="build-changes">

  2158. <span id="whatsnew311-build-changes"></span><h2>Build Changes<a class="headerlink" href="#build-changes" title="Link to this heading">¶</a></h2>

  2159. <ul>

  2160. <li><p>CPython now has <span class="target" id="index-33"></span><a class="pep reference external" href="https://peps.python.org/pep-0011/"><strong>PEP 11</strong></a> <span class="target" id="index-34"></span><a class="pep reference external" href="https://peps.python.org/pep-0011/#tier-3"><strong>Tier 3 support</strong></a> for

  2161. cross compiling to the <a class="reference external" href="https://webassembly.org/">WebAssembly</a> platforms

  2162. <a class="reference external" href="https://emscripten.org/">Emscripten</a>

  2163. (<code class="docutils literal notranslate"><span class="pre">wasm32-unknown-emscripten</span></code>, i.e. Python in the browser)

  2164. and <a class="reference external" href="https://wasi.dev/">WebAssembly System Interface (WASI)</a>

  2165. (<code class="docutils literal notranslate"><span class="pre">wasm32-unknown-wasi</span></code>).

  2166. The effort is inspired by previous work like <a class="reference external" href="https://pyodide.org/">Pyodide</a>.

  2167. These platforms provide a limited subset of POSIX APIs; Python standard

  2168. libraries features and modules related to networking, processes, threading,

  2169. signals, mmap, and users/groups are not available or don’t work.

  2170. (Emscripten contributed by Christian Heimes and Ethan Smith in <a class="reference external" href="https://github.com/python/cpython/issues/84461">gh-84461</a>

  2171. and WASI contributed by Christian Heimes in <a class="reference external" href="https://github.com/python/cpython/issues/90473">gh-90473</a>;

  2172. platforms promoted in <a class="reference external" href="https://github.com/python/cpython/issues/95085">gh-95085</a>)</p></li>

  2173. <li><p>Building CPython now requires:</p>

  2174. <ul class="simple">

  2175. <li><p>A <a class="reference external" href="https://en.cppreference.com/w/c/11">C11</a> compiler and standard library.

  2176. <a class="reference external" href="https://en.wikipedia.org/wiki/C11_(C_standard_revision)#Optional_features">Optional C11 features</a>

  2177. are not required.

  2178. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46656">bpo-46656</a>,

  2179. <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45440">bpo-45440</a> and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46640">bpo-46640</a>.)</p></li>

  2180. <li><p>Support for <a class="reference external" href="https://en.wikipedia.org/wiki/IEEE_754">IEEE 754</a>

  2181. floating point numbers.

  2182. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46917">bpo-46917</a>.)</p></li>

  2183. </ul>

  2184. </li>

  2185. <li><p>The <code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_NO_NAN</span></code> macro has been removed.

  2186. Since CPython now requires IEEE 754 floats, NaN values are always available.

  2187. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46656">bpo-46656</a>.)</p></li>

  2188. <li><p>The <a class="reference internal" href="../library/tkinter.html#module-tkinter" title="tkinter: Interface to Tcl/Tk for graphical user interfaces"><code class="xref py py-mod docutils literal notranslate"><span class="pre">tkinter</span></code></a> package now requires <a class="reference external" href="https://www.tcl.tk">Tcl/Tk</a>

  2189. version 8.5.12 or newer.

  2190. (Contributed by Serhiy Storchaka in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46996">bpo-46996</a>.)</p></li>

  2191. <li><p>Build dependencies, compiler flags, and linker flags for most stdlib

  2192. extension modules are now detected by <strong class="program">configure</strong>. libffi, libnsl,

  2193. libsqlite3, zlib, bzip2, liblzma, libcrypt, Tcl/Tk, and uuid flags

  2194. are detected by <a class="reference external" href="https://www.freedesktop.org/wiki/Software/pkg-config/">pkg-config</a> (when available).

  2195. <a class="reference internal" href="../library/tkinter.html#module-tkinter" title="tkinter: Interface to Tcl/Tk for graphical user interfaces"><code class="xref py py-mod docutils literal notranslate"><span class="pre">tkinter</span></code></a> now requires a pkg-config command

  2196. to detect development settings for <a class="reference external" href="https://www.tcl.tk">Tcl/Tk</a> headers and libraries.

  2197. (Contributed by Christian Heimes and Erlend Egeberg Aasland in

  2198. <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45847">bpo-45847</a>, <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45747">bpo-45747</a>, and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45763">bpo-45763</a>.)</p></li>

  2199. <li><p>libpython is no longer linked against libcrypt.

  2200. (Contributed by Mike Gilbert in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45433">bpo-45433</a>.)</p></li>

  2201. <li><p>CPython can now be built with the

  2202. <a class="reference external" href="https://clang.llvm.org/docs/ThinLTO.html">ThinLTO</a> option

  2203. via passing <code class="docutils literal notranslate"><span class="pre">thin</span></code> to <a class="reference internal" href="../using/configure.html#cmdoption-with-lto"><code class="xref std std-option docutils literal notranslate"><span class="pre">--with-lto</span></code></a>, i.e. <code class="docutils literal notranslate"><span class="pre">--with-lto=thin</span></code>.

  2204. (Contributed by Donghee Na and Brett Holman in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44340">bpo-44340</a>.)</p></li>

  2205. <li><p>Freelists for object structs can now be disabled. A new <strong class="program">configure</strong>

  2206. option <a class="reference internal" href="../using/configure.html#cmdoption-without-freelists"><code class="xref std std-option docutils literal notranslate"><span class="pre">--without-freelists</span></code></a> can be used to disable all freelists

  2207. except empty tuple singleton.

  2208. (Contributed by Christian Heimes in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45522">bpo-45522</a>.)</p></li>

  2209. <li><p><code class="docutils literal notranslate"><span class="pre">Modules/Setup</span></code> and <code class="docutils literal notranslate"><span class="pre">Modules/makesetup</span></code> have been improved and tied up.

  2210. Extension modules can now be built through <code class="docutils literal notranslate"><span class="pre">makesetup</span></code>. All except some

  2211. test modules can be linked statically into a main binary or library.

  2212. (Contributed by Brett Cannon and Christian Heimes in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45548">bpo-45548</a>,

  2213. <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45570">bpo-45570</a>, <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45571">bpo-45571</a>, and <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43974">bpo-43974</a>.)</p>

  2214. <div class="admonition note">

  2215. <p class="admonition-title">Note</p>

  2216. <p>Use the environment variables <code class="xref std std-envvar docutils literal notranslate"><span class="pre">TCLTK_CFLAGS</span></code> and

  2217. <code class="xref std std-envvar docutils literal notranslate"><span class="pre">TCLTK_LIBS</span></code> to manually specify the location of Tcl/Tk headers

  2218. and libraries. The <strong class="program">configure</strong> options

  2219. <code class="xref std std-option docutils literal notranslate"><span class="pre">--with-tcltk-includes</span></code> and <code class="xref std std-option docutils literal notranslate"><span class="pre">--with-tcltk-libs</span></code>

  2220. have been removed.</p>

  2221. <p>On RHEL 7 and CentOS 7 the development packages do not provide <code class="docutils literal notranslate"><span class="pre">tcl.pc</span></code>

  2222. and <code class="docutils literal notranslate"><span class="pre">tk.pc</span></code>; use <code class="docutils literal notranslate"><span class="pre">TCLTK_LIBS=&quot;-ltk8.5</span> <span class="pre">-ltkstub8.5</span> <span class="pre">-ltcl8.5&quot;</span></code>.

  2223. The directory <code class="docutils literal notranslate"><span class="pre">Misc/rhel7</span></code> contains <code class="docutils literal notranslate"><span class="pre">.pc</span></code> files and instructions

  2224. on how to build Python with RHEL 7’s and CentOS 7’s Tcl/Tk and OpenSSL.</p>

  2225. </div>

  2226. </li>

  2227. <li><p>CPython will now use 30-bit digits by default for the Python <a class="reference internal" href="../library/functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate"><span class="pre">int</span></code></a>

  2228. implementation. Previously, the default was to use 30-bit digits on platforms

  2229. with <code class="docutils literal notranslate"><span class="pre">SIZEOF_VOID_P</span> <span class="pre">&gt;=</span> <span class="pre">8</span></code>, and 15-bit digits otherwise. It’s still possible

  2230. to explicitly request use of 15-bit digits via either the

  2231. <a class="reference internal" href="../using/configure.html#cmdoption-enable-big-digits"><code class="xref std std-option docutils literal notranslate"><span class="pre">--enable-big-digits</span></code></a> option to the configure script

  2232. or (for Windows) the <code class="docutils literal notranslate"><span class="pre">PYLONG_BITS_IN_DIGIT</span></code> variable in <code class="docutils literal notranslate"><span class="pre">PC/pyconfig.h</span></code>,

  2233. but this option may be removed at some point in the future.

  2234. (Contributed by Mark Dickinson in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45569">bpo-45569</a>.)</p></li>

  2235. </ul>

  2236. </section>

  2237. <section id="c-api-changes">

  2238. <span id="whatsnew311-c-api"></span><h2>C API Changes<a class="headerlink" href="#c-api-changes" title="Link to this heading">¶</a></h2>

  2239. <section id="whatsnew311-c-api-new-features">

  2240. <span id="id5"></span><h3>New Features<a class="headerlink" href="#whatsnew311-c-api-new-features" title="Link to this heading">¶</a></h3>

  2241. <ul>

  2242. <li><p>Add a new <a class="reference internal" href="../c-api/type.html#c.PyType_GetName" title="PyType_GetName"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GetName()</span></code></a> function to get type’s short name.

  2243. (Contributed by Hai Shi in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=42035">bpo-42035</a>.)</p></li>

  2244. <li><p>Add a new <a class="reference internal" href="../c-api/type.html#c.PyType_GetQualName" title="PyType_GetQualName"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GetQualName()</span></code></a> function to get type’s qualified name.

  2245. (Contributed by Hai Shi in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=42035">bpo-42035</a>.)</p></li>

  2246. <li><p>Add new <a class="reference internal" href="../c-api/init.html#c.PyThreadState_EnterTracing" title="PyThreadState_EnterTracing"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyThreadState_EnterTracing()</span></code></a> and

  2247. <a class="reference internal" href="../c-api/init.html#c.PyThreadState_LeaveTracing" title="PyThreadState_LeaveTracing"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyThreadState_LeaveTracing()</span></code></a> functions to the limited C API to

  2248. suspend and resume tracing and profiling.

  2249. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43760">bpo-43760</a>.)</p></li>

  2250. <li><p>Added the <a class="reference internal" href="../c-api/apiabiversion.html#c.Py_Version" title="Py_Version"><code class="xref c c-data docutils literal notranslate"><span class="pre">Py_Version</span></code></a> constant which bears the same value as

  2251. <a class="reference internal" href="../c-api/apiabiversion.html#c.PY_VERSION_HEX" title="PY_VERSION_HEX"><code class="xref c c-macro docutils literal notranslate"><span class="pre">PY_VERSION_HEX</span></code></a>.

  2252. (Contributed by  Gabriele N. Tornetta in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43931">bpo-43931</a>.)</p></li>

  2253. <li><p><a class="reference internal" href="../c-api/buffer.html#c.Py_buffer" title="Py_buffer"><code class="xref c c-type docutils literal notranslate"><span class="pre">Py_buffer</span></code></a> and APIs are now part of the limited API and the stable

  2254. ABI:</p>

  2255. <ul class="simple">

  2256. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyObject_CheckBuffer" title="PyObject_CheckBuffer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CheckBuffer()</span></code></a></p></li>

  2257. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyObject_GetBuffer" title="PyObject_GetBuffer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_GetBuffer()</span></code></a></p></li>

  2258. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_GetPointer" title="PyBuffer_GetPointer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_GetPointer()</span></code></a></p></li>

  2259. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_SizeFromFormat" title="PyBuffer_SizeFromFormat"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_SizeFromFormat()</span></code></a></p></li>

  2260. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_ToContiguous" title="PyBuffer_ToContiguous"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_ToContiguous()</span></code></a></p></li>

  2261. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_FromContiguous" title="PyBuffer_FromContiguous"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_FromContiguous()</span></code></a></p></li>

  2262. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyObject_CopyData" title="PyObject_CopyData"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CopyData()</span></code></a></p></li>

  2263. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_IsContiguous" title="PyBuffer_IsContiguous"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_IsContiguous()</span></code></a></p></li>

  2264. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_FillContiguousStrides" title="PyBuffer_FillContiguousStrides"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_FillContiguousStrides()</span></code></a></p></li>

  2265. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_FillInfo" title="PyBuffer_FillInfo"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_FillInfo()</span></code></a></p></li>

  2266. <li><p><a class="reference internal" href="../c-api/buffer.html#c.PyBuffer_Release" title="PyBuffer_Release"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBuffer_Release()</span></code></a></p></li>

  2267. <li><p><a class="reference internal" href="../c-api/memoryview.html#c.PyMemoryView_FromBuffer" title="PyMemoryView_FromBuffer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromBuffer()</span></code></a></p></li>

  2268. <li><p><a class="reference internal" href="../c-api/typeobj.html#c.PyBufferProcs.bf_getbuffer" title="PyBufferProcs.bf_getbuffer"><code class="xref c c-member docutils literal notranslate"><span class="pre">bf_getbuffer</span></code></a> and

  2269. <a class="reference internal" href="../c-api/typeobj.html#c.PyBufferProcs.bf_releasebuffer" title="PyBufferProcs.bf_releasebuffer"><code class="xref c c-member docutils literal notranslate"><span class="pre">bf_releasebuffer</span></code></a> type slots</p></li>

  2270. </ul>

  2271. <p>(Contributed by Christian Heimes in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45459">bpo-45459</a>.)</p>

  2272. </li>

  2273. <li><p>Added the <a class="reference internal" href="../c-api/type.html#c.PyType_GetModuleByDef" title="PyType_GetModuleByDef"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_GetModuleByDef()</span></code></a> function, used to get the module

  2274. in which a method was defined, in cases where this information is not

  2275. available directly (via <a class="reference internal" href="../c-api/structures.html#c.PyCMethod" title="PyCMethod"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyCMethod</span></code></a>).

  2276. (Contributed by Petr Viktorin in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46613">bpo-46613</a>.)</p></li>

  2277. <li><p>Add new functions to pack and unpack C double (serialize and deserialize):

  2278. <a class="reference internal" href="../c-api/float.html#c.PyFloat_Pack2" title="PyFloat_Pack2"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFloat_Pack2()</span></code></a>, <a class="reference internal" href="../c-api/float.html#c.PyFloat_Pack4" title="PyFloat_Pack4"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFloat_Pack4()</span></code></a>, <a class="reference internal" href="../c-api/float.html#c.PyFloat_Pack8" title="PyFloat_Pack8"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFloat_Pack8()</span></code></a>,

  2279. <a class="reference internal" href="../c-api/float.html#c.PyFloat_Unpack2" title="PyFloat_Unpack2"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFloat_Unpack2()</span></code></a>, <a class="reference internal" href="../c-api/float.html#c.PyFloat_Unpack4" title="PyFloat_Unpack4"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFloat_Unpack4()</span></code></a> and

  2280. <a class="reference internal" href="../c-api/float.html#c.PyFloat_Unpack8" title="PyFloat_Unpack8"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFloat_Unpack8()</span></code></a>.

  2281. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46906">bpo-46906</a>.)</p></li>

  2282. <li><p>Add new functions to get frame object attributes:

  2283. <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetBuiltins" title="PyFrame_GetBuiltins"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetBuiltins()</span></code></a>, <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetGenerator" title="PyFrame_GetGenerator"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetGenerator()</span></code></a>,

  2284. <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetGlobals" title="PyFrame_GetGlobals"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetGlobals()</span></code></a>, <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLasti" title="PyFrame_GetLasti"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLasti()</span></code></a>.</p></li>

  2285. <li><p>Added two new functions to get and set the active exception instance:

  2286. <a class="reference internal" href="../c-api/exceptions.html#c.PyErr_GetHandledException" title="PyErr_GetHandledException"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_GetHandledException()</span></code></a> and <a class="reference internal" href="../c-api/exceptions.html#c.PyErr_SetHandledException" title="PyErr_SetHandledException"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_SetHandledException()</span></code></a>.

  2287. These are alternatives to <a class="reference internal" href="../c-api/exceptions.html#c.PyErr_SetExcInfo" title="PyErr_SetExcInfo"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_SetExcInfo()</span></code></a> and

  2288. <a class="reference internal" href="../c-api/exceptions.html#c.PyErr_GetExcInfo" title="PyErr_GetExcInfo"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_GetExcInfo()</span></code></a> which work with the legacy 3-tuple

  2289. representation of exceptions.

  2290. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46343">bpo-46343</a>.)</p></li>

  2291. <li><p>Added the <a class="reference internal" href="../c-api/init_config.html#c.PyConfig.safe_path" title="PyConfig.safe_path"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyConfig.safe_path</span></code></a> member.

  2292. (Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/57684">gh-57684</a>.)</p></li>

  2293. </ul>

  2294. </section>

  2295. <section id="whatsnew311-c-api-porting">

  2296. <span id="id6"></span><h3>Porting to Python 3.11<a class="headerlink" href="#whatsnew311-c-api-porting" title="Link to this heading">¶</a></h3>

  2297. <ul id="whatsnew311-pep670">

  2298. <li><p>Some macros have been converted to static inline functions to avoid

  2299. <a class="reference external" href="https://gcc.gnu.org/onlinedocs/cpp/Macro-Pitfalls.html">macro pitfalls</a>.

  2300. The change should be mostly transparent to users,

  2301. as the replacement functions will cast their arguments to the expected types

  2302. to avoid compiler warnings due to static type checks.

  2303. However, when the limited C API is set to &gt;=3.11,

  2304. these casts are not done,

  2305. and callers will need to cast arguments to their expected types.

  2306. See <span class="target" id="index-35"></span><a class="pep reference external" href="https://peps.python.org/pep-0670/"><strong>PEP 670</strong></a> for more details.

  2307. (Contributed by Victor Stinner and Erlend E. Aasland in <a class="reference external" href="https://github.com/python/cpython/issues/89653">gh-89653</a>.)</p></li>

  2308. <li><p><a class="reference internal" href="../c-api/exceptions.html#c.PyErr_SetExcInfo" title="PyErr_SetExcInfo"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_SetExcInfo()</span></code></a> no longer uses the <code class="docutils literal notranslate"><span class="pre">type</span></code> and <code class="docutils literal notranslate"><span class="pre">traceback</span></code>

  2309. arguments, the interpreter now derives those values from the exception

  2310. instance (the <code class="docutils literal notranslate"><span class="pre">value</span></code> argument). The function still steals references

  2311. of all three arguments.

  2312. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45711">bpo-45711</a>.)</p></li>

  2313. <li><p><a class="reference internal" href="../c-api/exceptions.html#c.PyErr_GetExcInfo" title="PyErr_GetExcInfo"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyErr_GetExcInfo()</span></code></a> now derives the <code class="docutils literal notranslate"><span class="pre">type</span></code> and <code class="docutils literal notranslate"><span class="pre">traceback</span></code>

  2314. fields of the result from the exception instance (the <code class="docutils literal notranslate"><span class="pre">value</span></code> field).

  2315. (Contributed by Irit Katriel in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45711">bpo-45711</a>.)</p></li>

  2316. <li><p><a class="reference internal" href="../c-api/import.html#c._frozen" title="_frozen"><code class="xref c c-struct docutils literal notranslate"><span class="pre">_frozen</span></code></a> has a new <code class="docutils literal notranslate"><span class="pre">is_package</span></code> field to indicate whether

  2317. or not the frozen module is a package.  Previously, a negative value

  2318. in the <code class="docutils literal notranslate"><span class="pre">size</span></code> field was the indicator.  Now only non-negative values

  2319. be used for <code class="docutils literal notranslate"><span class="pre">size</span></code>.

  2320. (Contributed by Kumar Aditya in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46608">bpo-46608</a>.)</p></li>

  2321. <li><p><a class="reference internal" href="../c-api/init.html#c._PyFrameEvalFunction" title="_PyFrameEvalFunction"><code class="xref c c-func docutils literal notranslate"><span class="pre">_PyFrameEvalFunction()</span></code></a> now takes <code class="docutils literal notranslate"><span class="pre">_PyInterpreterFrame*</span></code>

  2322. as its second parameter, instead of <code class="docutils literal notranslate"><span class="pre">PyFrameObject*</span></code>.

  2323. See <span class="target" id="index-36"></span><a class="pep reference external" href="https://peps.python.org/pep-0523/"><strong>PEP 523</strong></a> for more details of how to use this function pointer type.</p></li>

  2324. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_New()</span></code> and <code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_NewWithPosOnlyArgs()</span></code> now take

  2325. an additional <code class="docutils literal notranslate"><span class="pre">exception_table</span></code> argument.

  2326. Using these functions should be avoided, if at all possible.

  2327. To get a custom code object: create a code object using the compiler,

  2328. then get a modified version with the <code class="docutils literal notranslate"><span class="pre">replace</span></code> method.</p></li>

  2329. <li><p><a class="reference internal" href="../c-api/code.html#c.PyCodeObject" title="PyCodeObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyCodeObject</span></code></a> no longer has the <code class="docutils literal notranslate"><span class="pre">co_code</span></code>, <code class="docutils literal notranslate"><span class="pre">co_varnames</span></code>,

  2330. <code class="docutils literal notranslate"><span class="pre">co_cellvars</span></code> and <code class="docutils literal notranslate"><span class="pre">co_freevars</span></code> fields.  Instead, use

  2331. <a class="reference internal" href="../c-api/code.html#c.PyCode_GetCode" title="PyCode_GetCode"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_GetCode()</span></code></a>, <a class="reference internal" href="../c-api/code.html#c.PyCode_GetVarnames" title="PyCode_GetVarnames"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_GetVarnames()</span></code></a>,

  2332. <a class="reference internal" href="../c-api/code.html#c.PyCode_GetCellvars" title="PyCode_GetCellvars"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_GetCellvars()</span></code></a> and <a class="reference internal" href="../c-api/code.html#c.PyCode_GetFreevars" title="PyCode_GetFreevars"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyCode_GetFreevars()</span></code></a> respectively

  2333. to access them via the C API.

  2334. (Contributed by Brandt Bucher in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46841">bpo-46841</a> and Ken Jin in <a class="reference external" href="https://github.com/python/cpython/issues/92154">gh-92154</a>

  2335. and <a class="reference external" href="https://github.com/python/cpython/issues/94936">gh-94936</a>.)</p></li>

  2336. <li><p>The old trashcan macros (<code class="docutils literal notranslate"><span class="pre">Py_TRASHCAN_SAFE_BEGIN</span></code>/<code class="docutils literal notranslate"><span class="pre">Py_TRASHCAN_SAFE_END</span></code>)

  2337. are now deprecated. They should be replaced by the new macros

  2338. <code class="docutils literal notranslate"><span class="pre">Py_TRASHCAN_BEGIN</span></code> and <code class="docutils literal notranslate"><span class="pre">Py_TRASHCAN_END</span></code>.</p>

  2339. <p>A tp_dealloc function that has the old macros, such as:</p>

  2340. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">static</span> <span class="n">void</span>

  2341. <span class="n">mytype_dealloc</span><span class="p">(</span><span class="n">mytype</span> <span class="o">*</span><span class="n">p</span><span class="p">)</span>

  2342. <span class="p">{</span>

  2343.     <span class="n">PyObject_GC_UnTrack</span><span class="p">(</span><span class="n">p</span><span class="p">);</span>

  2344.     <span class="n">Py_TRASHCAN_SAFE_BEGIN</span><span class="p">(</span><span class="n">p</span><span class="p">);</span>

  2345.     <span class="o">...</span>

  2346.     <span class="n">Py_TRASHCAN_SAFE_END</span>

  2347. <span class="p">}</span>

  2348. </pre></div>

  2349. </div>

  2350. <p>should migrate to the new macros as follows:</p>

  2351. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="n">static</span> <span class="n">void</span>

  2352. <span class="n">mytype_dealloc</span><span class="p">(</span><span class="n">mytype</span> <span class="o">*</span><span class="n">p</span><span class="p">)</span>

  2353. <span class="p">{</span>

  2354.     <span class="n">PyObject_GC_UnTrack</span><span class="p">(</span><span class="n">p</span><span class="p">);</span>

  2355.     <span class="n">Py_TRASHCAN_BEGIN</span><span class="p">(</span><span class="n">p</span><span class="p">,</span> <span class="n">mytype_dealloc</span><span class="p">)</span>

  2356.     <span class="o">...</span>

  2357.     <span class="n">Py_TRASHCAN_END</span>

  2358. <span class="p">}</span>

  2359. </pre></div>

  2360. </div>

  2361. <p>Note that <code class="docutils literal notranslate"><span class="pre">Py_TRASHCAN_BEGIN</span></code> has a second argument which

  2362. should be the deallocation function it is in.</p>

  2363. <p>To support older Python versions in the same codebase, you

  2364. can define the following macros and use them throughout

  2365. the code (credit: these were copied from the <code class="docutils literal notranslate"><span class="pre">mypy</span></code> codebase):</p>

  2366. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &gt;= 0x03080000</span>

  2367. <span class="c1">#  define CPy_TRASHCAN_BEGIN(op, dealloc) Py_TRASHCAN_BEGIN(op, dealloc)</span>

  2368. <span class="c1">#  define CPy_TRASHCAN_END(op) Py_TRASHCAN_END</span>

  2369. <span class="c1">#else</span>

  2370. <span class="c1">#  define CPy_TRASHCAN_BEGIN(op, dealloc) Py_TRASHCAN_SAFE_BEGIN(op)</span>

  2371. <span class="c1">#  define CPy_TRASHCAN_END(op) Py_TRASHCAN_SAFE_END(op)</span>

  2372. <span class="c1">#endif</span>

  2373. </pre></div>

  2374. </div>

  2375. </li>

  2376. <li><p>The <a class="reference internal" href="../c-api/type.html#c.PyType_Ready" title="PyType_Ready"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyType_Ready()</span></code></a> function now raises an error if a type is defined

  2377. with the <a class="reference internal" href="../c-api/typeobj.html#c.Py_TPFLAGS_HAVE_GC" title="Py_TPFLAGS_HAVE_GC"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_TPFLAGS_HAVE_GC</span></code></a> flag set but has no traverse function

  2378. (<a class="reference internal" href="../c-api/typeobj.html#c.PyTypeObject.tp_traverse" title="PyTypeObject.tp_traverse"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyTypeObject.tp_traverse</span></code></a>).

  2379. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44263">bpo-44263</a>.)</p></li>

  2380. <li><p>Heap types with the <a class="reference internal" href="../c-api/typeobj.html#c.Py_TPFLAGS_IMMUTABLETYPE" title="Py_TPFLAGS_IMMUTABLETYPE"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_TPFLAGS_IMMUTABLETYPE</span></code></a> flag can now inherit

  2381. the <span class="target" id="index-37"></span><a class="pep reference external" href="https://peps.python.org/pep-0590/"><strong>PEP 590</strong></a> vectorcall protocol.  Previously, this was only possible for

  2382. <a class="reference internal" href="../c-api/typeobj.html#static-types"><span class="std std-ref">static types</span></a>.

  2383. (Contributed by Erlend E. Aasland in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43908">bpo-43908</a>)</p></li>

  2384. <li><p>Since <a class="reference internal" href="../c-api/structures.html#c.Py_TYPE" title="Py_TYPE"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_TYPE()</span></code></a> is changed to a inline static function,

  2385. <code class="docutils literal notranslate"><span class="pre">Py_TYPE(obj)</span> <span class="pre">=</span> <span class="pre">new_type</span></code> must be replaced with

  2386. <code class="docutils literal notranslate"><span class="pre">Py_SET_TYPE(obj,</span> <span class="pre">new_type)</span></code>: see the <a class="reference internal" href="../c-api/structures.html#c.Py_SET_TYPE" title="Py_SET_TYPE"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SET_TYPE()</span></code></a> function

  2387. (available since Python 3.9). For backward compatibility, this macro can be

  2388. used:</p>

  2389. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &lt; 0x030900A4 &amp;&amp; !defined(Py_SET_TYPE)</span>

  2390. <span class="n">static</span> <span class="n">inline</span> <span class="n">void</span> <span class="n">_Py_SET_TYPE</span><span class="p">(</span><span class="n">PyObject</span> <span class="o">*</span><span class="n">ob</span><span class="p">,</span> <span class="n">PyTypeObject</span> <span class="o">*</span><span class="nb">type</span><span class="p">)</span>

  2391. <span class="p">{</span> <span class="n">ob</span><span class="o">-&gt;</span><span class="n">ob_type</span> <span class="o">=</span> <span class="nb">type</span><span class="p">;</span> <span class="p">}</span>

  2392. <span class="c1">#define Py_SET_TYPE(ob, type) _Py_SET_TYPE((PyObject*)(ob), type)</span>

  2393. <span class="c1">#endif</span>

  2394. </pre></div>

  2395. </div>

  2396. <p>(Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=39573">bpo-39573</a>.)</p>

  2397. </li>

  2398. <li><p>Since <a class="reference internal" href="../c-api/structures.html#c.Py_SIZE" title="Py_SIZE"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SIZE()</span></code></a> is changed to a inline static function,

  2399. <code class="docutils literal notranslate"><span class="pre">Py_SIZE(obj)</span> <span class="pre">=</span> <span class="pre">new_size</span></code> must be replaced with

  2400. <code class="docutils literal notranslate"><span class="pre">Py_SET_SIZE(obj,</span> <span class="pre">new_size)</span></code>: see the <a class="reference internal" href="../c-api/structures.html#c.Py_SET_SIZE" title="Py_SET_SIZE"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SET_SIZE()</span></code></a> function

  2401. (available since Python 3.9). For backward compatibility, this macro can be

  2402. used:</p>

  2403. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &lt; 0x030900A4 &amp;&amp; !defined(Py_SET_SIZE)</span>

  2404. <span class="n">static</span> <span class="n">inline</span> <span class="n">void</span> <span class="n">_Py_SET_SIZE</span><span class="p">(</span><span class="n">PyVarObject</span> <span class="o">*</span><span class="n">ob</span><span class="p">,</span> <span class="n">Py_ssize_t</span> <span class="n">size</span><span class="p">)</span>

  2405. <span class="p">{</span> <span class="n">ob</span><span class="o">-&gt;</span><span class="n">ob_size</span> <span class="o">=</span> <span class="n">size</span><span class="p">;</span> <span class="p">}</span>

  2406. <span class="c1">#define Py_SET_SIZE(ob, size) _Py_SET_SIZE((PyVarObject*)(ob), size)</span>

  2407. <span class="c1">#endif</span>

  2408. </pre></div>

  2409. </div>

  2410. <p>(Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=39573">bpo-39573</a>.)</p>

  2411. </li>

  2412. <li><p><code class="docutils literal notranslate"><span class="pre">&lt;Python.h&gt;</span></code> no longer includes the header files <code class="docutils literal notranslate"><span class="pre">&lt;stdlib.h&gt;</span></code>,

  2413. <code class="docutils literal notranslate"><span class="pre">&lt;stdio.h&gt;</span></code>, <code class="docutils literal notranslate"><span class="pre">&lt;errno.h&gt;</span></code> and <code class="docutils literal notranslate"><span class="pre">&lt;string.h&gt;</span></code> when the <code class="docutils literal notranslate"><span class="pre">Py_LIMITED_API</span></code>

  2414. macro is set to <code class="docutils literal notranslate"><span class="pre">0x030b0000</span></code> (Python 3.11) or higher. C extensions should

  2415. explicitly include the header files after <code class="docutils literal notranslate"><span class="pre">#include</span> <span class="pre">&lt;Python.h&gt;</span></code>.

  2416. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45434">bpo-45434</a>.)</p></li>

  2417. <li><p>The non-limited API files <code class="docutils literal notranslate"><span class="pre">cellobject.h</span></code>, <code class="docutils literal notranslate"><span class="pre">classobject.h</span></code>, <code class="docutils literal notranslate"><span class="pre">code.h</span></code>, <code class="docutils literal notranslate"><span class="pre">context.h</span></code>,

  2418. <code class="docutils literal notranslate"><span class="pre">funcobject.h</span></code>, <code class="docutils literal notranslate"><span class="pre">genobject.h</span></code> and <code class="docutils literal notranslate"><span class="pre">longintrepr.h</span></code> have been moved to

  2419. the <code class="docutils literal notranslate"><span class="pre">Include/cpython</span></code> directory. Moreover, the <code class="docutils literal notranslate"><span class="pre">eval.h</span></code> header file was

  2420. removed. These files must not be included directly, as they are already

  2421. included in <code class="docutils literal notranslate"><span class="pre">Python.h</span></code>: <a class="reference internal" href="../c-api/intro.html#api-includes"><span class="std std-ref">Include Files</span></a>. If they have

  2422. been included directly, consider including <code class="docutils literal notranslate"><span class="pre">Python.h</span></code> instead.

  2423. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=35134">bpo-35134</a>.)</p></li>

  2424. <li><p>The <code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_CHECK_INTERNED()</span></code> macro has been excluded from the

  2425. limited C API. It was never usable there, because it used internal structures

  2426. which are not available in the limited C API.

  2427. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46007">bpo-46007</a>.)</p></li>

  2428. <li><p>The following frame functions and type are now directly available with

  2429. <code class="docutils literal notranslate"><span class="pre">#include</span> <span class="pre">&lt;Python.h&gt;</span></code>, it’s no longer needed to add

  2430. <code class="docutils literal notranslate"><span class="pre">#include</span> <span class="pre">&lt;frameobject.h&gt;</span></code>:</p>

  2431. <ul class="simple">

  2432. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_Check" title="PyFrame_Check"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_Check()</span></code></a></p></li>

  2433. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetBack" title="PyFrame_GetBack"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetBack()</span></code></a></p></li>

  2434. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetBuiltins" title="PyFrame_GetBuiltins"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetBuiltins()</span></code></a></p></li>

  2435. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetGenerator" title="PyFrame_GetGenerator"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetGenerator()</span></code></a></p></li>

  2436. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetGlobals" title="PyFrame_GetGlobals"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetGlobals()</span></code></a></p></li>

  2437. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLasti" title="PyFrame_GetLasti"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLasti()</span></code></a></p></li>

  2438. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLocals" title="PyFrame_GetLocals"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLocals()</span></code></a></p></li>

  2439. <li><p><a class="reference internal" href="../c-api/frame.html#c.PyFrame_Type" title="PyFrame_Type"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFrame_Type</span></code></a></p></li>

  2440. </ul>

  2441. <p>(Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/93937">gh-93937</a>.)</p>

  2442. </li>

  2443. </ul>

  2444. <ul id="pyframeobject-3-11-hiding">

  2445. <li><p>The <a class="reference internal" href="../c-api/frame.html#c.PyFrameObject" title="PyFrameObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFrameObject</span></code></a> structure members have been removed from the

  2446. public C API.</p>

  2447. <p>While the documentation notes that the <a class="reference internal" href="../c-api/frame.html#c.PyFrameObject" title="PyFrameObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFrameObject</span></code></a> fields are

  2448. subject to change at any time, they have been stable for a long time and were

  2449. used in several popular extensions.</p>

  2450. <p>In Python 3.11, the frame struct was reorganized to allow performance

  2451. optimizations. Some fields were removed entirely, as they were details of the

  2452. old implementation.</p>

  2453. <p><a class="reference internal" href="../c-api/frame.html#c.PyFrameObject" title="PyFrameObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyFrameObject</span></code></a> fields:</p>

  2454. <ul class="simple">

  2455. <li><p><code class="docutils literal notranslate"><span class="pre">f_back</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetBack" title="PyFrame_GetBack"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetBack()</span></code></a>.</p></li>

  2456. <li><p><code class="docutils literal notranslate"><span class="pre">f_blockstack</span></code>: removed.</p></li>

  2457. <li><p><code class="docutils literal notranslate"><span class="pre">f_builtins</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetBuiltins" title="PyFrame_GetBuiltins"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetBuiltins()</span></code></a>.</p></li>

  2458. <li><p><code class="docutils literal notranslate"><span class="pre">f_code</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetCode" title="PyFrame_GetCode"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetCode()</span></code></a>.</p></li>

  2459. <li><p><code class="docutils literal notranslate"><span class="pre">f_gen</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetGenerator" title="PyFrame_GetGenerator"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetGenerator()</span></code></a>.</p></li>

  2460. <li><p><code class="docutils literal notranslate"><span class="pre">f_globals</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetGlobals" title="PyFrame_GetGlobals"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetGlobals()</span></code></a>.</p></li>

  2461. <li><p><code class="docutils literal notranslate"><span class="pre">f_iblock</span></code>: removed.</p></li>

  2462. <li><p><code class="docutils literal notranslate"><span class="pre">f_lasti</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLasti" title="PyFrame_GetLasti"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLasti()</span></code></a>.

  2463. Code using <code class="docutils literal notranslate"><span class="pre">f_lasti</span></code> with <code class="docutils literal notranslate"><span class="pre">PyCode_Addr2Line()</span></code> should use

  2464. <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLineNumber" title="PyFrame_GetLineNumber"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLineNumber()</span></code></a> instead; it may be faster.</p></li>

  2465. <li><p><code class="docutils literal notranslate"><span class="pre">f_lineno</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLineNumber" title="PyFrame_GetLineNumber"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLineNumber()</span></code></a></p></li>

  2466. <li><p><code class="docutils literal notranslate"><span class="pre">f_locals</span></code>: use <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLocals" title="PyFrame_GetLocals"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLocals()</span></code></a>.</p></li>

  2467. <li><p><code class="docutils literal notranslate"><span class="pre">f_stackdepth</span></code>: removed.</p></li>

  2468. <li><p><code class="docutils literal notranslate"><span class="pre">f_state</span></code>: no public API (renamed to <code class="docutils literal notranslate"><span class="pre">f_frame.f_state</span></code>).</p></li>

  2469. <li><p><code class="docutils literal notranslate"><span class="pre">f_trace</span></code>: no public API.</p></li>

  2470. <li><p><code class="docutils literal notranslate"><span class="pre">f_trace_lines</span></code>: use <code class="docutils literal notranslate"><span class="pre">PyObject_GetAttrString((PyObject*)frame,</span> <span class="pre">&quot;f_trace_lines&quot;)</span></code>.</p></li>

  2471. <li><p><code class="docutils literal notranslate"><span class="pre">f_trace_opcodes</span></code>: use <code class="docutils literal notranslate"><span class="pre">PyObject_GetAttrString((PyObject*)frame,</span> <span class="pre">&quot;f_trace_opcodes&quot;)</span></code>.</p></li>

  2472. <li><p><code class="docutils literal notranslate"><span class="pre">f_localsplus</span></code>: no public API (renamed to <code class="docutils literal notranslate"><span class="pre">f_frame.localsplus</span></code>).</p></li>

  2473. <li><p><code class="docutils literal notranslate"><span class="pre">f_valuestack</span></code>: removed.</p></li>

  2474. </ul>

  2475. <p>The Python frame object is now created lazily. A side effect is that the

  2476. <a class="reference internal" href="../reference/datamodel.html#frame.f_back" title="frame.f_back"><code class="xref py py-attr docutils literal notranslate"><span class="pre">f_back</span></code></a> member must not be accessed directly,

  2477. since its value is now also

  2478. computed lazily. The <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetBack" title="PyFrame_GetBack"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetBack()</span></code></a> function must be called

  2479. instead.</p>

  2480. <p>Debuggers that accessed the <a class="reference internal" href="../reference/datamodel.html#frame.f_locals" title="frame.f_locals"><code class="xref py py-attr docutils literal notranslate"><span class="pre">f_locals</span></code></a> directly <em>must</em> call

  2481. <a class="reference internal" href="../c-api/frame.html#c.PyFrame_GetLocals" title="PyFrame_GetLocals"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_GetLocals()</span></code></a> instead. They no longer need to call

  2482. <code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_FastToLocalsWithError()</span></code> or <code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_LocalsToFast()</span></code>,

  2483. in fact they should not call those functions. The necessary updating of the

  2484. frame is now managed by the virtual machine.</p>

  2485. <p>Code defining <code class="docutils literal notranslate"><span class="pre">PyFrame_GetCode()</span></code> on Python 3.8 and older:</p>

  2486. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &lt; 0x030900B1</span>

  2487. <span class="n">static</span> <span class="n">inline</span> <span class="n">PyCodeObject</span><span class="o">*</span> <span class="n">PyFrame_GetCode</span><span class="p">(</span><span class="n">PyFrameObject</span> <span class="o">*</span><span class="n">frame</span><span class="p">)</span>

  2488. <span class="p">{</span>

  2489.     <span class="n">Py_INCREF</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">f_code</span><span class="p">);</span>

  2490.     <span class="k">return</span> <span class="n">frame</span><span class="o">-&gt;</span><span class="n">f_code</span><span class="p">;</span>

  2491. <span class="p">}</span>

  2492. <span class="c1">#endif</span>

  2493. </pre></div>

  2494. </div>

  2495. <p>Code defining <code class="docutils literal notranslate"><span class="pre">PyFrame_GetBack()</span></code> on Python 3.8 and older:</p>

  2496. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &lt; 0x030900B1</span>

  2497. <span class="n">static</span> <span class="n">inline</span> <span class="n">PyFrameObject</span><span class="o">*</span> <span class="n">PyFrame_GetBack</span><span class="p">(</span><span class="n">PyFrameObject</span> <span class="o">*</span><span class="n">frame</span><span class="p">)</span>

  2498. <span class="p">{</span>

  2499.     <span class="n">Py_XINCREF</span><span class="p">(</span><span class="n">frame</span><span class="o">-&gt;</span><span class="n">f_back</span><span class="p">);</span>

  2500.     <span class="k">return</span> <span class="n">frame</span><span class="o">-&gt;</span><span class="n">f_back</span><span class="p">;</span>

  2501. <span class="p">}</span>

  2502. <span class="c1">#endif</span>

  2503. </pre></div>

  2504. </div>

  2505. <p>Or use the <a class="reference external" href="https://github.com/python/pythoncapi-compat">pythoncapi_compat project</a> to get these two

  2506. functions on older Python versions.</p>

  2507. </li>

  2508. <li><p>Changes of the <a class="reference internal" href="../c-api/init.html#c.PyThreadState" title="PyThreadState"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyThreadState</span></code></a> structure members:</p>

  2509. <ul class="simple">

  2510. <li><p><code class="docutils literal notranslate"><span class="pre">frame</span></code>: removed, use <a class="reference internal" href="../c-api/init.html#c.PyThreadState_GetFrame" title="PyThreadState_GetFrame"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyThreadState_GetFrame()</span></code></a> (function added

  2511. to Python 3.9 by <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40429">bpo-40429</a>).

  2512. Warning: the function returns a <a class="reference internal" href="../glossary.html#term-strong-reference"><span class="xref std std-term">strong reference</span></a>, need to call

  2513. <a class="reference internal" href="../c-api/refcounting.html#c.Py_XDECREF" title="Py_XDECREF"><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_XDECREF()</span></code></a>.</p></li>

  2514. <li><p><code class="docutils literal notranslate"><span class="pre">tracing</span></code>: changed, use <a class="reference internal" href="../c-api/init.html#c.PyThreadState_EnterTracing" title="PyThreadState_EnterTracing"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyThreadState_EnterTracing()</span></code></a>

  2515. and <a class="reference internal" href="../c-api/init.html#c.PyThreadState_LeaveTracing" title="PyThreadState_LeaveTracing"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyThreadState_LeaveTracing()</span></code></a>

  2516. (functions added to Python 3.11 by <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=43760">bpo-43760</a>).</p></li>

  2517. <li><p><code class="docutils literal notranslate"><span class="pre">recursion_depth</span></code>: removed,

  2518. use <code class="docutils literal notranslate"><span class="pre">(tstate-&gt;recursion_limit</span> <span class="pre">-</span> <span class="pre">tstate-&gt;recursion_remaining)</span></code> instead.</p></li>

  2519. <li><p><code class="docutils literal notranslate"><span class="pre">stackcheck_counter</span></code>: removed.</p></li>

  2520. </ul>

  2521. <p>Code defining <code class="docutils literal notranslate"><span class="pre">PyThreadState_GetFrame()</span></code> on Python 3.8 and older:</p>

  2522. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &lt; 0x030900B1</span>

  2523. <span class="n">static</span> <span class="n">inline</span> <span class="n">PyFrameObject</span><span class="o">*</span> <span class="n">PyThreadState_GetFrame</span><span class="p">(</span><span class="n">PyThreadState</span> <span class="o">*</span><span class="n">tstate</span><span class="p">)</span>

  2524. <span class="p">{</span>

  2525.     <span class="n">Py_XINCREF</span><span class="p">(</span><span class="n">tstate</span><span class="o">-&gt;</span><span class="n">frame</span><span class="p">);</span>

  2526.     <span class="k">return</span> <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">frame</span><span class="p">;</span>

  2527. <span class="p">}</span>

  2528. <span class="c1">#endif</span>

  2529. </pre></div>

  2530. </div>

  2531. <p>Code defining <code class="docutils literal notranslate"><span class="pre">PyThreadState_EnterTracing()</span></code> and

  2532. <code class="docutils literal notranslate"><span class="pre">PyThreadState_LeaveTracing()</span></code> on Python 3.10 and older:</p>

  2533. <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1">#if PY_VERSION_HEX &lt; 0x030B00A2</span>

  2534. <span class="n">static</span> <span class="n">inline</span> <span class="n">void</span> <span class="n">PyThreadState_EnterTracing</span><span class="p">(</span><span class="n">PyThreadState</span> <span class="o">*</span><span class="n">tstate</span><span class="p">)</span>

  2535. <span class="p">{</span>

  2536.     <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">tracing</span><span class="o">++</span><span class="p">;</span>

  2537. <span class="c1">#if PY_VERSION_HEX &gt;= 0x030A00A1</span>

  2538.     <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">cframe</span><span class="o">-&gt;</span><span class="n">use_tracing</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span>

  2539. <span class="c1">#else</span>

  2540.     <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">use_tracing</span> <span class="o">=</span> <span class="mi">0</span><span class="p">;</span>

  2541. <span class="c1">#endif</span>

  2542. <span class="p">}</span>

  2543. 

  2544. <span class="n">static</span> <span class="n">inline</span> <span class="n">void</span> <span class="n">PyThreadState_LeaveTracing</span><span class="p">(</span><span class="n">PyThreadState</span> <span class="o">*</span><span class="n">tstate</span><span class="p">)</span>

  2545. <span class="p">{</span>

  2546.     <span class="nb">int</span> <span class="n">use_tracing</span> <span class="o">=</span> <span class="p">(</span><span class="n">tstate</span><span class="o">-&gt;</span><span class="n">c_tracefunc</span> <span class="o">!=</span> <span class="n">NULL</span> <span class="o">||</span> <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">c_profilefunc</span> <span class="o">!=</span> <span class="n">NULL</span><span class="p">);</span>

  2547.     <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">tracing</span><span class="o">--</span><span class="p">;</span>

  2548. <span class="c1">#if PY_VERSION_HEX &gt;= 0x030A00A1</span>

  2549.     <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">cframe</span><span class="o">-&gt;</span><span class="n">use_tracing</span> <span class="o">=</span> <span class="n">use_tracing</span><span class="p">;</span>

  2550. <span class="c1">#else</span>

  2551.     <span class="n">tstate</span><span class="o">-&gt;</span><span class="n">use_tracing</span> <span class="o">=</span> <span class="n">use_tracing</span><span class="p">;</span>

  2552. <span class="c1">#endif</span>

  2553. <span class="p">}</span>

  2554. <span class="c1">#endif</span>

  2555. </pre></div>

  2556. </div>

  2557. <p>Or use <a class="reference external" href="https://github.com/python/pythoncapi-compat">the pythoncapi-compat project</a> to get these functions

  2558. on old Python functions.</p>

  2559. </li>

  2560. <li><p>Distributors are encouraged to build Python with the optimized Blake2

  2561. library <a class="reference external" href="https://www.blake2.net/">libb2</a>.</p></li>

  2562. <li><p>The <a class="reference internal" href="../c-api/init_config.html#c.PyConfig.module_search_paths_set" title="PyConfig.module_search_paths_set"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyConfig.module_search_paths_set</span></code></a> field must now be set to 1 for

  2563. initialization to use <a class="reference internal" href="../c-api/init_config.html#c.PyConfig.module_search_paths" title="PyConfig.module_search_paths"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyConfig.module_search_paths</span></code></a> to initialize

  2564. <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a>. Otherwise, initialization will recalculate the path and replace

  2565. any values added to <code class="docutils literal notranslate"><span class="pre">module_search_paths</span></code>.</p></li>

  2566. <li><p><a class="reference internal" href="../c-api/init_config.html#c.PyConfig_Read" title="PyConfig_Read"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyConfig_Read()</span></code></a> no longer calculates the initial search path, and will not

  2567. fill any values into <a class="reference internal" href="../c-api/init_config.html#c.PyConfig.module_search_paths" title="PyConfig.module_search_paths"><code class="xref c c-member docutils literal notranslate"><span class="pre">PyConfig.module_search_paths</span></code></a>. To calculate default

  2568. paths and then modify them, finish initialization and use <a class="reference internal" href="../c-api/sys.html#c.PySys_GetObject" title="PySys_GetObject"><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_GetObject()</span></code></a>

  2569. to retrieve <a class="reference internal" href="../library/sys.html#sys.path" title="sys.path"><code class="xref py py-data docutils literal notranslate"><span class="pre">sys.path</span></code></a> as a Python list object and modify it directly.</p></li>

  2570. </ul>

  2571. </section>

  2572. <section id="whatsnew311-c-api-deprecated">

  2573. <span id="id7"></span><h3>Deprecated<a class="headerlink" href="#whatsnew311-c-api-deprecated" title="Link to this heading">¶</a></h3>

  2574. <ul>

  2575. <li><p>Deprecate the following functions to configure the Python initialization:</p>

  2576. <ul class="simple">

  2577. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_AddWarnOptionUnicode()</span></code></p></li>

  2578. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_AddWarnOption()</span></code></p></li>

  2579. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_AddXOption()</span></code></p></li>

  2580. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_HasWarnOptions()</span></code></p></li>

  2581. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_SetArgvEx()</span></code></p></li>

  2582. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_SetArgv()</span></code></p></li>

  2583. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PySys_SetPath()</span></code></p></li>

  2584. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SetPath()</span></code></p></li>

  2585. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SetProgramName()</span></code></p></li>

  2586. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SetPythonHome()</span></code></p></li>

  2587. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">Py_SetStandardStreamEncoding()</span></code></p></li>

  2588. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">_Py_SetProgramFullPath()</span></code></p></li>

  2589. </ul>

  2590. <p>Use the new <a class="reference internal" href="../c-api/init_config.html#c.PyConfig" title="PyConfig"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyConfig</span></code></a> API of the <a class="reference internal" href="../c-api/init_config.html#init-config"><span class="std std-ref">Python Initialization Configuration</span></a> instead (<span class="target" id="index-38"></span><a class="pep reference external" href="https://peps.python.org/pep-0587/"><strong>PEP 587</strong></a>).

  2591. (Contributed by Victor Stinner in <a class="reference external" href="https://github.com/python/cpython/issues/88279">gh-88279</a>.)</p>

  2592. </li>

  2593. <li><p>Deprecate the <code class="docutils literal notranslate"><span class="pre">ob_shash</span></code> member of the <a class="reference internal" href="../c-api/bytes.html#c.PyBytesObject" title="PyBytesObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyBytesObject</span></code></a>. Use <a class="reference internal" href="../c-api/object.html#c.PyObject_Hash" title="PyObject_Hash"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Hash()</span></code></a> instead.

  2594. (Contributed by Inada Naoki in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=46864">bpo-46864</a>.)</p></li>

  2595. </ul>

  2596. </section>

  2597. <section id="whatsnew311-c-api-pending-removal">

  2598. <span id="id8"></span><h3>Pending Removal in Python 3.12<a class="headerlink" href="#whatsnew311-c-api-pending-removal" title="Link to this heading">¶</a></h3>

  2599. <p>The following C APIs have been deprecated in earlier Python releases,

  2600. and will be removed in Python 3.12.</p>

  2601. <ul class="simple">

  2602. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_AS_DATA()</span></code></p></li>

  2603. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_AS_UNICODE()</span></code></p></li>

  2604. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_AsUnicodeAndSize()</span></code></p></li>

  2605. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_AsUnicode()</span></code></p></li>

  2606. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_FromUnicode()</span></code></p></li>

  2607. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_GET_DATA_SIZE()</span></code></p></li>

  2608. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_GET_SIZE()</span></code></p></li>

  2609. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_GetSize()</span></code></p></li>

  2610. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_IS_COMPACT()</span></code></p></li>

  2611. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_IS_READY()</span></code></p></li>

  2612. <li><p><a class="reference internal" href="../c-api/unicode.html#c.PyUnicode_READY" title="PyUnicode_READY"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_READY()</span></code></a></p></li>

  2613. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_WSTR_LENGTH()</span></code></p></li>

  2614. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">_PyUnicode_AsUnicode()</span></code></p></li>

  2615. <li><p><code class="xref c c-macro docutils literal notranslate"><span class="pre">PyUnicode_WCHAR_KIND</span></code></p></li>

  2616. <li><p><a class="reference internal" href="../c-api/unicode.html#c.PyUnicodeObject" title="PyUnicodeObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyUnicodeObject</span></code></a></p></li>

  2617. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyUnicode_InternImmortal()</span></code></p></li>

  2618. </ul>

  2619. </section>

  2620. <section id="whatsnew311-c-api-removed">

  2621. <span id="id9"></span><h3>Removed<a class="headerlink" href="#whatsnew311-c-api-removed" title="Link to this heading">¶</a></h3>

  2622. <ul>

  2623. <li><p><code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_BlockSetup()</span></code> and <code class="xref c c-func docutils literal notranslate"><span class="pre">PyFrame_BlockPop()</span></code> have been

  2624. removed.

  2625. (Contributed by Mark Shannon in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40222">bpo-40222</a>.)</p></li>

  2626. <li><p>Remove the following math macros using the <code class="docutils literal notranslate"><span class="pre">errno</span></code> variable:</p>

  2627. <ul class="simple">

  2628. <li><p><code class="docutils literal notranslate"><span class="pre">Py_ADJUST_ERANGE1()</span></code></p></li>

  2629. <li><p><code class="docutils literal notranslate"><span class="pre">Py_ADJUST_ERANGE2()</span></code></p></li>

  2630. <li><p><code class="docutils literal notranslate"><span class="pre">Py_OVERFLOWED()</span></code></p></li>

  2631. <li><p><code class="docutils literal notranslate"><span class="pre">Py_SET_ERANGE_IF_OVERFLOW()</span></code></p></li>

  2632. <li><p><code class="docutils literal notranslate"><span class="pre">Py_SET_ERRNO_ON_MATH_ERROR()</span></code></p></li>

  2633. </ul>

  2634. <p>(Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45412">bpo-45412</a>.)</p>

  2635. </li>

  2636. <li><p>Remove <code class="docutils literal notranslate"><span class="pre">Py_UNICODE_COPY()</span></code> and <code class="docutils literal notranslate"><span class="pre">Py_UNICODE_FILL()</span></code> macros, deprecated

  2637. since Python 3.3. Use <code class="docutils literal notranslate"><span class="pre">PyUnicode_CopyCharacters()</span></code> or <code class="docutils literal notranslate"><span class="pre">memcpy()</span></code>

  2638. (<code class="docutils literal notranslate"><span class="pre">wchar_t*</span></code> string), and <code class="docutils literal notranslate"><span class="pre">PyUnicode_Fill()</span></code> functions instead.

  2639. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=41123">bpo-41123</a>.)</p></li>

  2640. <li><p>Remove the <code class="docutils literal notranslate"><span class="pre">pystrhex.h</span></code> header file. It only contains private functions.

  2641. C extensions should only include the main <code class="docutils literal notranslate"><span class="pre">&lt;Python.h&gt;</span></code> header file.

  2642. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45434">bpo-45434</a>.)</p></li>

  2643. <li><p>Remove the <code class="docutils literal notranslate"><span class="pre">Py_FORCE_DOUBLE()</span></code> macro. It was used by the

  2644. <code class="docutils literal notranslate"><span class="pre">Py_IS_INFINITY()</span></code> macro.

  2645. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45440">bpo-45440</a>.)</p></li>

  2646. <li><p>The following items are no longer available when <a class="reference internal" href="../c-api/stable.html#c.Py_LIMITED_API" title="Py_LIMITED_API"><code class="xref c c-macro docutils literal notranslate"><span class="pre">Py_LIMITED_API</span></code></a>

  2647. is defined:</p>

  2648. <ul class="simple">

  2649. <li><p><a class="reference internal" href="../c-api/marshal.html#c.PyMarshal_WriteLongToFile" title="PyMarshal_WriteLongToFile"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMarshal_WriteLongToFile()</span></code></a></p></li>

  2650. <li><p><a class="reference internal" href="../c-api/marshal.html#c.PyMarshal_WriteObjectToFile" title="PyMarshal_WriteObjectToFile"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMarshal_WriteObjectToFile()</span></code></a></p></li>

  2651. <li><p><a class="reference internal" href="../c-api/marshal.html#c.PyMarshal_ReadObjectFromString" title="PyMarshal_ReadObjectFromString"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMarshal_ReadObjectFromString()</span></code></a></p></li>

  2652. <li><p><a class="reference internal" href="../c-api/marshal.html#c.PyMarshal_WriteObjectToString" title="PyMarshal_WriteObjectToString"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMarshal_WriteObjectToString()</span></code></a></p></li>

  2653. <li><p>the <code class="docutils literal notranslate"><span class="pre">Py_MARSHAL_VERSION</span></code> macro</p></li>

  2654. </ul>

  2655. <p>These are not part of the <a class="reference internal" href="../c-api/stable.html#limited-api-list"><span class="std std-ref">limited API</span></a>.</p>

  2656. <p>(Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45474">bpo-45474</a>.)</p>

  2657. </li>

  2658. <li><p>Exclude <a class="reference internal" href="../c-api/weakref.html#c.PyWeakref_GET_OBJECT" title="PyWeakref_GET_OBJECT"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyWeakref_GET_OBJECT()</span></code></a> from the limited C API. It never

  2659. worked since the <code class="xref c c-type docutils literal notranslate"><span class="pre">PyWeakReference</span></code> structure is opaque in the

  2660. limited C API.

  2661. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=35134">bpo-35134</a>.)</p></li>

  2662. <li><p>Remove the <code class="docutils literal notranslate"><span class="pre">PyHeapType_GET_MEMBERS()</span></code> macro. It was exposed in the

  2663. public C API by mistake, it must only be used by Python internally.

  2664. Use the <code class="docutils literal notranslate"><span class="pre">PyTypeObject.tp_members</span></code> member instead.

  2665. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=40170">bpo-40170</a>.)</p></li>

  2666. <li><p>Remove the <code class="docutils literal notranslate"><span class="pre">HAVE_PY_SET_53BIT_PRECISION</span></code> macro (moved to the internal C

  2667. API).

  2668. (Contributed by Victor Stinner in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=45412">bpo-45412</a>.)</p></li>

  2669. </ul>

  2670. <ul id="whatsnew311-pep624">

  2671. <li><p>Remove the <a class="reference internal" href="../c-api/unicode.html#c.Py_UNICODE" title="Py_UNICODE"><code class="xref c c-type docutils literal notranslate"><span class="pre">Py_UNICODE</span></code></a> encoder APIs,

  2672. as they have been deprecated since Python 3.3,

  2673. are little used

  2674. and are inefficient relative to the recommended alternatives.</p>

  2675. <p>The removed functions are:</p>

  2676. <ul class="simple">

  2677. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_Encode()</span></code></p></li>

  2678. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeASCII()</span></code></p></li>

  2679. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeLatin1()</span></code></p></li>

  2680. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeUTF7()</span></code></p></li>

  2681. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeUTF8()</span></code></p></li>

  2682. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeUTF16()</span></code></p></li>

  2683. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeUTF32()</span></code></p></li>

  2684. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeUnicodeEscape()</span></code></p></li>

  2685. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeRawUnicodeEscape()</span></code></p></li>

  2686. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeCharmap()</span></code></p></li>

  2687. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_TranslateCharmap()</span></code></p></li>

  2688. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_EncodeDecimal()</span></code></p></li>

  2689. <li><p><code class="xref py py-func docutils literal notranslate"><span class="pre">PyUnicode_TransformDecimalToASCII()</span></code></p></li>

  2690. </ul>

  2691. <p>See <span class="target" id="index-39"></span><a class="pep reference external" href="https://peps.python.org/pep-0624/"><strong>PEP 624</strong></a> for details and

  2692. <span class="target" id="index-40"></span><a class="pep reference external" href="https://peps.python.org/pep-0624/#alternative-apis"><strong>migration guidance</strong></a>.

  2693. (Contributed by Inada Naoki in <a class="reference external" href="https://bugs.python.org/issue?&#64;action=redirect&amp;bpo=44029">bpo-44029</a>.)</p>

  2694. </li>

  2695. </ul>

  2696. </section>

  2697. </section>

  2698. <section id="notable-changes-in-3-11-4">

  2699. <h2>Notable changes in 3.11.4<a class="headerlink" href="#notable-changes-in-3-11-4" title="Link to this heading">¶</a></h2>

  2700. <section id="tarfile">

  2701. <h3>tarfile<a class="headerlink" href="#tarfile" title="Link to this heading">¶</a></h3>

  2702. <ul class="simple">

  2703. <li><p>The extraction methods in <a class="reference internal" href="../library/tarfile.html#module-tarfile" title="tarfile: Read and write tar-format archive files."><code class="xref py py-mod docutils literal notranslate"><span class="pre">tarfile</span></code></a>, and <a class="reference internal" href="../library/shutil.html#shutil.unpack_archive" title="shutil.unpack_archive"><code class="xref py py-func docutils literal notranslate"><span class="pre">shutil.unpack_archive()</span></code></a>,

  2704. have a new a <em>filter</em> argument that allows limiting tar features than may be

  2705. surprising or dangerous, such as creating files outside the destination

  2706. directory.

  2707. See <a class="reference internal" href="../library/tarfile.html#tarfile-extraction-filter"><span class="std std-ref">Extraction filters</span></a> for details.

  2708. In Python 3.12, use without the <em>filter</em> argument will show a

  2709. <a class="reference internal" href="../library/exceptions.html#DeprecationWarning" title="DeprecationWarning"><code class="xref py py-exc docutils literal notranslate"><span class="pre">DeprecationWarning</span></code></a>.

  2710. In Python 3.14, the default will switch to <code class="docutils literal notranslate"><span class="pre">'data'</span></code>.

  2711. (Contributed by Petr Viktorin in <span class="target" id="index-41"></span><a class="pep reference external" href="https://peps.python.org/pep-0706/"><strong>PEP 706</strong></a>.)</p></li>

  2712. </ul>

  2713. </section>

  2714. </section>

  2715. <section id="notable-changes-in-3-11-5">

  2716. <h2>Notable changes in 3.11.5<a class="headerlink" href="#notable-changes-in-3-11-5" title="Link to this heading">¶</a></h2>

  2717. <section id="openssl">

  2718. <h3>OpenSSL<a class="headerlink" href="#openssl" title="Link to this heading">¶</a></h3>

  2719. <ul class="simple">

  2720. <li><p>Windows builds and macOS installers from python.org now use OpenSSL 3.0.</p></li>

  2721. </ul>

  2722. </section>

  2723. </section>

  2724. </section>

  2725. 

  2726. 

  2727.             <div class="clearer"></div>

  2728.           </div>

  2729.         </div>

  2730.       </div>

  2731.       <div class="sphinxsidebar" role="navigation" aria-label="main navigation">

  2732.         <div class="sphinxsidebarwrapper">

  2733.   <div>

  2734.     <h3><a href="../contents.html">Table of Contents</a></h3>

  2735.     <ul>

  2736. <li><a class="reference internal" href="#">What’s New In Python 3.11</a><ul>

  2737. <li><a class="reference internal" href="#summary-release-highlights">Summary – Release highlights</a></li>

  2738. <li><a class="reference internal" href="#new-features">New Features</a><ul>

  2739. <li><a class="reference internal" href="#pep-657-fine-grained-error-locations-in-tracebacks">PEP 657: Fine-grained error locations in tracebacks</a></li>

  2740. <li><a class="reference internal" href="#pep-654-exception-groups-and-except">PEP 654: Exception Groups and <code class="docutils literal notranslate"><span class="pre">except*</span></code></a></li>

  2741. <li><a class="reference internal" href="#pep-678-exceptions-can-be-enriched-with-notes">PEP 678: Exceptions can be enriched with notes</a></li>

  2742. <li><a class="reference internal" href="#windows-py-exe-launcher-improvements">Windows <code class="docutils literal notranslate"><span class="pre">py.exe</span></code> launcher improvements</a></li>

  2743. </ul>

  2744. </li>

  2745. <li><a class="reference internal" href="#new-features-related-to-type-hints">New Features Related to Type Hints</a><ul>

  2746. <li><a class="reference internal" href="#pep-646-variadic-generics">PEP 646: Variadic generics</a></li>

  2747. <li><a class="reference internal" href="#pep-655-marking-individual-typeddict-items-as-required-or-not-required">PEP 655: Marking individual <code class="docutils literal notranslate"><span class="pre">TypedDict</span></code> items as required or not-required</a></li>

  2748. <li><a class="reference internal" href="#pep-673-self-type">PEP 673: <code class="docutils literal notranslate"><span class="pre">Self</span></code> type</a></li>

  2749. <li><a class="reference internal" href="#pep-675-arbitrary-literal-string-type">PEP 675: Arbitrary literal string type</a></li>

  2750. <li><a class="reference internal" href="#pep-681-data-class-transforms">PEP 681: Data class transforms</a></li>

  2751. <li><a class="reference internal" href="#pep-563-may-not-be-the-future">PEP 563 may not be the future</a></li>

  2752. </ul>

  2753. </li>

  2754. <li><a class="reference internal" href="#other-language-changes">Other Language Changes</a></li>

  2755. <li><a class="reference internal" href="#other-cpython-implementation-changes">Other CPython Implementation Changes</a></li>

  2756. <li><a class="reference internal" href="#new-modules">New Modules</a></li>

  2757. <li><a class="reference internal" href="#improved-modules">Improved Modules</a><ul>

  2758. <li><a class="reference internal" href="#asyncio">asyncio</a></li>

  2759. <li><a class="reference internal" href="#contextlib">contextlib</a></li>

  2760. <li><a class="reference internal" href="#dataclasses">dataclasses</a></li>

  2761. <li><a class="reference internal" href="#datetime">datetime</a></li>

  2762. <li><a class="reference internal" href="#enum">enum</a></li>

  2763. <li><a class="reference internal" href="#fcntl">fcntl</a></li>

  2764. <li><a class="reference internal" href="#fractions">fractions</a></li>

  2765. <li><a class="reference internal" href="#functools">functools</a></li>

  2766. <li><a class="reference internal" href="#hashlib">hashlib</a></li>

  2767. <li><a class="reference internal" href="#whatsnew311-idle">IDLE and idlelib</a></li>

  2768. <li><a class="reference internal" href="#inspect">inspect</a></li>

  2769. <li><a class="reference internal" href="#locale">locale</a></li>

  2770. <li><a class="reference internal" href="#logging">logging</a></li>

  2771. <li><a class="reference internal" href="#math">math</a></li>

  2772. <li><a class="reference internal" href="#operator">operator</a></li>

  2773. <li><a class="reference internal" href="#os">os</a></li>

  2774. <li><a class="reference internal" href="#pathlib">pathlib</a></li>

  2775. <li><a class="reference internal" href="#re">re</a></li>

  2776. <li><a class="reference internal" href="#shutil">shutil</a></li>

  2777. <li><a class="reference internal" href="#socket">socket</a></li>

  2778. <li><a class="reference internal" href="#sqlite3">sqlite3</a></li>

  2779. <li><a class="reference internal" href="#string">string</a></li>

  2780. <li><a class="reference internal" href="#sys">sys</a></li>

  2781. <li><a class="reference internal" href="#sysconfig">sysconfig</a></li>

  2782. <li><a class="reference internal" href="#tempfile">tempfile</a></li>

  2783. <li><a class="reference internal" href="#threading">threading</a></li>

  2784. <li><a class="reference internal" href="#time">time</a></li>

  2785. <li><a class="reference internal" href="#tkinter">tkinter</a></li>

  2786. <li><a class="reference internal" href="#traceback">traceback</a></li>

  2787. <li><a class="reference internal" href="#typing">typing</a></li>

  2788. <li><a class="reference internal" href="#unicodedata">unicodedata</a></li>

  2789. <li><a class="reference internal" href="#unittest">unittest</a></li>

  2790. <li><a class="reference internal" href="#venv">venv</a></li>

  2791. <li><a class="reference internal" href="#warnings">warnings</a></li>

  2792. <li><a class="reference internal" href="#zipfile">zipfile</a></li>

  2793. </ul>

  2794. </li>

  2795. <li><a class="reference internal" href="#optimizations">Optimizations</a></li>

  2796. <li><a class="reference internal" href="#faster-cpython">Faster CPython</a><ul>

  2797. <li><a class="reference internal" href="#faster-startup">Faster Startup</a><ul>

  2798. <li><a class="reference internal" href="#frozen-imports-static-code-objects">Frozen imports / Static code objects</a></li>

  2799. </ul>

  2800. </li>

  2801. <li><a class="reference internal" href="#faster-runtime">Faster Runtime</a><ul>

  2802. <li><a class="reference internal" href="#cheaper-lazy-python-frames">Cheaper, lazy Python frames</a></li>

  2803. <li><a class="reference internal" href="#inlined-python-function-calls">Inlined Python function calls</a></li>

  2804. <li><a class="reference internal" href="#pep-659-specializing-adaptive-interpreter">PEP 659: Specializing Adaptive Interpreter</a></li>

  2805. </ul>

  2806. </li>

  2807. <li><a class="reference internal" href="#misc">Misc</a></li>

  2808. <li><a class="reference internal" href="#faq">FAQ</a><ul>

  2809. <li><a class="reference internal" href="#how-should-i-write-my-code-to-utilize-these-speedups">How should I write my code to utilize these speedups?</a></li>

  2810. <li><a class="reference internal" href="#will-cpython-3-11-use-more-memory">Will CPython 3.11 use more memory?</a></li>

  2811. <li><a class="reference internal" href="#i-don-t-see-any-speedups-in-my-workload-why">I don’t see any speedups in my workload. Why?</a></li>

  2812. <li><a class="reference internal" href="#is-there-a-jit-compiler">Is there a JIT compiler?</a></li>

  2813. </ul>

  2814. </li>

  2815. <li><a class="reference internal" href="#about">About</a></li>

  2816. </ul>

  2817. </li>

  2818. <li><a class="reference internal" href="#cpython-bytecode-changes">CPython bytecode changes</a><ul>

  2819. <li><a class="reference internal" href="#new-opcodes">New opcodes</a></li>

  2820. <li><a class="reference internal" href="#replaced-opcodes">Replaced opcodes</a></li>

  2821. <li><a class="reference internal" href="#changed-removed-opcodes">Changed/removed opcodes</a></li>

  2822. </ul>

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  2826. <li><a class="reference internal" href="#modules">Modules</a></li>

  2827. <li><a class="reference internal" href="#standard-library">Standard Library</a></li>

  2828. </ul>

  2829. </li>

  2830. <li><a class="reference internal" href="#pending-removal-in-python-3-12">Pending Removal in Python 3.12</a></li>

  2831. <li><a class="reference internal" href="#removed">Removed</a></li>

  2832. <li><a class="reference internal" href="#porting-to-python-3-11">Porting to Python 3.11</a></li>

  2833. <li><a class="reference internal" href="#build-changes">Build Changes</a></li>

  2834. <li><a class="reference internal" href="#c-api-changes">C API Changes</a><ul>

  2835. <li><a class="reference internal" href="#whatsnew311-c-api-new-features">New Features</a></li>

  2836. <li><a class="reference internal" href="#whatsnew311-c-api-porting">Porting to Python 3.11</a></li>

  2837. <li><a class="reference internal" href="#whatsnew311-c-api-deprecated">Deprecated</a></li>

  2838. <li><a class="reference internal" href="#whatsnew311-c-api-pending-removal">Pending Removal in Python 3.12</a></li>

  2839. <li><a class="reference internal" href="#whatsnew311-c-api-removed">Removed</a></li>

  2840. </ul>

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