Team Ai
Apppublic

parthtamu/rag-code-assistant

sourceHugging Faceupdated 7mo agoView on Hugging Face
0likes
asyncio-policy.html528 linesDownload Raw Back to docs
1<!DOCTYPE html>2 3<html lang="en" data-content_root="../">4  <head>5    <meta charset="utf-8" />6    <meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="viewport" content="width=device-width, initial-scale=1" />7<meta property="og:title" content="Policies" />8<meta property="og:type" content="website" />9<meta property="og:url" content="https://docs.python.org/3/library/asyncio-policy.html" />10<meta property="og:site_name" content="Python documentation" />11<meta property="og:description" content="An event loop policy is a global object used to get and set the current event loop, as well as create new event loops. The default policy can be replaced with built-in alternatives to use different..." />12<meta property="og:image:width" content="1146" />13<meta property="og:image:height" content="600" />14<meta property="og:image" content="https://docs.python.org/3.15/_images/social_previews/summary_library_asyncio-policy_7192a5d0.png" />15<meta property="og:image:alt" content="An event loop policy is a global object used to get and set the current event loop, as well as create new event loops. The default policy can be replaced with built-in alternatives to use different..." />16<meta name="description" content="An event loop policy is a global object used to get and set the current event loop, as well as create new event loops. The default policy can be replaced with built-in alternatives to use different..." />17<meta name="twitter:card" content="summary_large_image" />18<meta name="theme-color" content="#3776ab">19 20    <title>Policies &#8212; Python 3.15.0a6 documentation</title><meta name="viewport" content="width=device-width, initial-scale=1.0">21    22    <link rel="stylesheet" type="text/css" href="../_static/pygments.css?v=b86133f3" />23    <link rel="stylesheet" type="text/css" href="../_static/classic.css?v=234b1a7c" />24    <link rel="stylesheet" type="text/css" href="../_static/pydoctheme.css?v=89a2f22a" />25    <link rel="stylesheet" type="text/css" href="../_static/profiling-sampling-visualization.css?v=0c2600ae" />26    <link id="pygments_dark_css" media="(prefers-color-scheme: dark)" rel="stylesheet" type="text/css" href="../_static/pygments_dark.css?v=5349f25f" />27    28    <script src="../_static/documentation_options.js?v=6b7c9ff5"></script>29    <script src="../_static/doctools.js?v=9bcbadda"></script>30    <script src="../_static/sphinx_highlight.js?v=dc90522c"></script>31    <script src="../_static/profiling-sampling-visualization.js?v=9811ed04"></script>32    33    <script src="../_static/sidebar.js"></script>34    35    <link rel="search" type="application/opensearchdescription+xml"36          title="Search within Python 3.15.0a6 documentation"37          href="../_static/opensearch.xml"/>38    <link rel="author" title="About these documents" href="../about.html" />39    <link rel="index" title="Index" href="../genindex.html" />40    <link rel="search" title="Search" href="../search.html" />41    <link rel="copyright" title="Copyright" href="../copyright.html" />42    <link rel="next" title="Platform Support" href="asyncio-platforms.html" />43    <link rel="prev" title="Transports and Protocols" href="asyncio-protocol.html" />44    45      46      <script defer file-types="bz2,epub,zip" data-domain="docs.python.org" src="https://analytics.python.org/js/script.file-downloads.outbound-links.js"></script>47      48      <link rel="canonical" href="https://docs.python.org/3/library/asyncio-policy.html">49      50    51 52    53    <style>54      @media only screen {55        table.full-width-table {56            width: 100%;57        }58      }59    </style>60<link rel="stylesheet" href="../_static/pydoctheme_dark.css" media="(prefers-color-scheme: dark)" id="pydoctheme_dark_css">61    <link rel="shortcut icon" type="image/png" href="../_static/py.svg">62            <script type="text/javascript" src="../_static/copybutton.js"></script>63            <script type="text/javascript" src="../_static/menu.js"></script>64            <script type="text/javascript" src="../_static/search-focus.js"></script>65            <script type="text/javascript" src="../_static/themetoggle.js"></script> 66            <script type="text/javascript" src="../_static/rtd_switcher.js"></script>67            <meta name="readthedocs-addons-api-version" content="1">68 69  </head>70<body>71<div class="mobile-nav">72    <input type="checkbox" id="menuToggler" class="toggler__input" aria-controls="navigation"73           aria-pressed="false" aria-expanded="false" role="button" aria-label="Menu">74    <nav class="nav-content" role="navigation">75        <label for="menuToggler" class="toggler__label">76            <span></span>77        </label>78        <span class="nav-items-wrapper">79            <a href="https://www.python.org/" class="nav-logo">80                <img src="../_static/py.svg" alt="Python logo">81            </a>82            <span class="version_switcher_placeholder"></span>83            <form role="search" class="search" action="../search.html" method="get">84                <svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24" class="search-icon">85                    <path fill-rule="nonzero" fill="currentColor" d="M15.5 14h-.79l-.28-.27a6.5 6.5 0 001.48-5.34c-.47-2.78-2.79-5-5.59-5.34a6.505 6.505 0 00-7.27 7.27c.34 2.8 2.56 5.12 5.34 5.59a6.5 6.5 0 005.34-1.48l.27.28v.79l4.25 4.25c.41.41 1.08.41 1.49 0 .41-.41.41-1.08 0-1.49L15.5 14zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14z"></path>86                </svg>87                <input placeholder="Quick search" aria-label="Quick search" type="search" name="q">88                <input type="submit" value="Go">89            </form>90        </span>91    </nav>92    <div class="menu-wrapper">93        <nav class="menu" role="navigation" aria-label="main navigation">94            <div class="language_switcher_placeholder"></div>95            96<label class="theme-selector-label">97    Theme98    <select class="theme-selector" oninput="activateTheme(this.value)">99        <option value="auto" selected>Auto</option>100        <option value="light">Light</option>101        <option value="dark">Dark</option>102    </select>103</label>104  <div>105    <h3><a href="../contents.html">Table of Contents</a></h3>106    <ul>107<li><a class="reference internal" href="#">Policies</a><ul>108<li><a class="reference internal" href="#getting-and-setting-the-policy">Getting and Setting the Policy</a></li>109<li><a class="reference internal" href="#policy-objects">Policy Objects</a></li>110<li><a class="reference internal" href="#custom-policies">Custom Policies</a></li>111</ul>112</li>113</ul>114 115  </div>116  <div>117    <h4>Previous topic</h4>118    <p class="topless"><a href="asyncio-protocol.html"119                          title="previous chapter">Transports and Protocols</a></p>120  </div>121  <div>122    <h4>Next topic</h4>123    <p class="topless"><a href="asyncio-platforms.html"124                          title="next chapter">Platform Support</a></p>125  </div>126  <script>127    document.addEventListener('DOMContentLoaded', () => {128        const title = document.querySelector('meta[property="og:title"]').content;129        const elements = document.querySelectorAll('.improvepage');130        const pageurl = window.location.href.split('?')[0];131        elements.forEach(element => {132            const url = new URL(element.href.split('?')[0].replace("-nojs", ""));133            url.searchParams.set('pagetitle', title);134            url.searchParams.set('pageurl', pageurl);135            url.searchParams.set('pagesource', "library/asyncio-policy.rst");136            element.href = url.toString();137        });138    });139  </script>140  <div role="note" aria-label="source link">141    <h3>This page</h3>142    <ul class="this-page-menu">143      <li><a href="../bugs.html">Report a bug</a></li>144      <li><a class="improvepage" href="../improve-page-nojs.html">Improve this page</a></li>145      <li>146        <a href="https://github.com/python/cpython/blob/main/Doc/library/asyncio-policy.rst?plain=1"147            rel="nofollow">Show source148        </a>149      </li>150      151    </ul>152  </div>153        </nav>154    </div>155</div>156 157  158    <div class="related" role="navigation" aria-label="Related">159      <h3>Navigation</h3>160      <ul>161        <li class="right" style="margin-right: 10px">162          <a href="../genindex.html" title="General Index"163             accesskey="I">index</a></li>164        <li class="right" >165          <a href="../py-modindex.html" title="Python Module Index"166             >modules</a> |</li>167        <li class="right" >168          <a href="asyncio-platforms.html" title="Platform Support"169             accesskey="N">next</a> |</li>170        <li class="right" >171          <a href="asyncio-protocol.html" title="Transports and Protocols"172             accesskey="P">previous</a> |</li>173 174          <li><img src="../_static/py.svg" alt="Python logo" style="vertical-align: middle; margin-top: -1px"></li>175          <li><a href="https://www.python.org/">Python</a> &#187;</li>176          <li class="switchers">177            <div class="language_switcher_placeholder"></div>178            <div class="version_switcher_placeholder"></div>179          </li>180          <li>181              182          </li>183    <li id="cpython-language-and-version">184      <a href="../index.html">3.15.0a6 Documentation</a> &#187;185    </li>186 187          <li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> &#187;</li>188          <li class="nav-item nav-item-2"><a href="ipc.html" >Networking and Interprocess Communication</a> &#187;</li>189          <li class="nav-item nav-item-3"><a href="asyncio.html" accesskey="U"><code class="xref py py-mod docutils literal notranslate"><span class="pre">asyncio</span></code> — Asynchronous I/O</a> &#187;</li>190        <li class="nav-item nav-item-this"><a href="">Policies</a></li>191                <li class="right">192                    193 194    <div class="inline-search" role="search">195        <form class="inline-search" action="../search.html" method="get">196          <input placeholder="Quick search" aria-label="Quick search" type="search" name="q" id="search-box">197          <input type="submit" value="Go">198        </form>199    </div>200                     |201                </li>202            <li class="right">203<label class="theme-selector-label">204    Theme205    <select class="theme-selector" oninput="activateTheme(this.value)">206        <option value="auto" selected>Auto</option>207        <option value="light">Light</option>208        <option value="dark">Dark</option>209    </select>210</label> |</li>211            212      </ul>213    </div>    214 215    <div class="document">216      <div class="documentwrapper">217        <div class="bodywrapper">218          <div class="body" role="main">219            220  <section id="policies">221<span id="asyncio-policies"></span><h1>Policies<a class="headerlink" href="#policies" title="Link to this heading">¶</a></h1>222<div class="admonition warning">223<p class="admonition-title">Warning</p>224<p>Policies are deprecated and will be removed in Python 3.16.225Users are encouraged to use the <a class="reference internal" href="asyncio-runner.html#asyncio.run" title="asyncio.run"><code class="xref py py-func docutils literal notranslate"><span class="pre">asyncio.run()</span></code></a> function226or the <a class="reference internal" href="asyncio-runner.html#asyncio.Runner" title="asyncio.Runner"><code class="xref py py-class docutils literal notranslate"><span class="pre">asyncio.Runner</span></code></a> with <em>loop_factory</em> to use227the desired loop implementation.</p>228</div>229<p>An event loop policy is a global object230used to get and set the current <a class="reference internal" href="asyncio-eventloop.html#asyncio-event-loop"><span class="std std-ref">event loop</span></a>,231as well as create new event loops.232The default policy can be <a class="reference internal" href="#asyncio-policy-get-set"><span class="std std-ref">replaced</span></a> with233<a class="reference internal" href="#asyncio-policy-builtin"><span class="std std-ref">built-in alternatives</span></a>234to use different event loop implementations,235or substituted by a <a class="reference internal" href="#asyncio-custom-policies"><span class="std std-ref">custom policy</span></a>236that can override these behaviors.</p>237<p>The <a class="reference internal" href="#asyncio-policy-objects"><span class="std std-ref">policy object</span></a>238gets and sets a separate event loop per <em>context</em>.239This is per-thread by default,240though custom policies could define <em>context</em> differently.</p>241<p>Custom event loop policies can control the behavior of242<a class="reference internal" href="asyncio-eventloop.html#asyncio.get_event_loop" title="asyncio.get_event_loop"><code class="xref py py-func docutils literal notranslate"><span class="pre">get_event_loop()</span></code></a>, <a class="reference internal" href="asyncio-eventloop.html#asyncio.set_event_loop" title="asyncio.set_event_loop"><code class="xref py py-func docutils literal notranslate"><span class="pre">set_event_loop()</span></code></a>, and <a class="reference internal" href="asyncio-eventloop.html#asyncio.new_event_loop" title="asyncio.new_event_loop"><code class="xref py py-func docutils literal notranslate"><span class="pre">new_event_loop()</span></code></a>.</p>243<p>Policy objects should implement the APIs defined244in the <a class="reference internal" href="#asyncio.AbstractEventLoopPolicy" title="asyncio.AbstractEventLoopPolicy"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractEventLoopPolicy</span></code></a> abstract base class.</p>245<section id="getting-and-setting-the-policy">246<span id="asyncio-policy-get-set"></span><h2>Getting and Setting the Policy<a class="headerlink" href="#getting-and-setting-the-policy" title="Link to this heading">¶</a></h2>247<p>The following functions can be used to get and set the policy248for the current process:</p>249<dl class="py function">250<dt class="sig sig-object py" id="asyncio.get_event_loop_policy">251<span class="sig-prename descclassname"><span class="pre">asyncio.</span></span><span class="sig-name descname"><span class="pre">get_event_loop_policy</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.get_event_loop_policy" title="Link to this definition">¶</a></dt>252<dd><p>Return the current process-wide policy.</p>253<div class="deprecated">254<p><span class="versionmodified deprecated">Deprecated since version 3.14: </span>The <code class="xref py py-func docutils literal notranslate"><span class="pre">get_event_loop_policy()</span></code> function is deprecated and255will be removed in Python 3.16.</p>256</div>257</dd></dl>258 259<dl class="py function">260<dt class="sig sig-object py" id="asyncio.set_event_loop_policy">261<span class="sig-prename descclassname"><span class="pre">asyncio.</span></span><span class="sig-name descname"><span class="pre">set_event_loop_policy</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">policy</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.set_event_loop_policy" title="Link to this definition">¶</a></dt>262<dd><p>Set the current process-wide policy to <em>policy</em>.</p>263<p>If <em>policy</em> is set to <code class="docutils literal notranslate"><span class="pre">None</span></code>, the default policy is restored.</p>264<div class="deprecated">265<p><span class="versionmodified deprecated">Deprecated since version 3.14: </span>The <code class="xref py py-func docutils literal notranslate"><span class="pre">set_event_loop_policy()</span></code> function is deprecated and266will be removed in Python 3.16.</p>267</div>268</dd></dl>269 270</section>271<section id="policy-objects">272<span id="asyncio-policy-objects"></span><h2>Policy Objects<a class="headerlink" href="#policy-objects" title="Link to this heading">¶</a></h2>273<p>The abstract event loop policy base class is defined as follows:</p>274<dl class="py class">275<dt class="sig sig-object py" id="asyncio.AbstractEventLoopPolicy">276<em class="property"><span class="k"><span class="pre">class</span></span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">asyncio.</span></span><span class="sig-name descname"><span class="pre">AbstractEventLoopPolicy</span></span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy" title="Link to this definition">¶</a></dt>277<dd><p>An abstract base class for asyncio policies.</p>278<dl class="py method">279<dt class="sig sig-object py" id="asyncio.AbstractEventLoopPolicy.get_event_loop">280<span class="sig-name descname"><span class="pre">get_event_loop</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.get_event_loop" title="Link to this definition">¶</a></dt>281<dd><p>Get the event loop for the current context.</p>282<p>Return an event loop object implementing the283<a class="reference internal" href="asyncio-eventloop.html#asyncio.AbstractEventLoop" title="asyncio.AbstractEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractEventLoop</span></code></a> interface.</p>284<p>This method should never return <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>285<div class="versionchanged">286<p><span class="versionmodified changed">Changed in version 3.6.</span></p>287</div>288</dd></dl>289 290<dl class="py method">291<dt class="sig sig-object py" id="asyncio.AbstractEventLoopPolicy.set_event_loop">292<span class="sig-name descname"><span class="pre">set_event_loop</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">loop</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.set_event_loop" title="Link to this definition">¶</a></dt>293<dd><p>Set the event loop for the current context to <em>loop</em>.</p>294</dd></dl>295 296<dl class="py method">297<dt class="sig sig-object py" id="asyncio.AbstractEventLoopPolicy.new_event_loop">298<span class="sig-name descname"><span class="pre">new_event_loop</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.AbstractEventLoopPolicy.new_event_loop" title="Link to this definition">¶</a></dt>299<dd><p>Create and return a new event loop object.</p>300<p>This method should never return <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>301</dd></dl>302 303<div class="deprecated">304<p><span class="versionmodified deprecated">Deprecated since version 3.14: </span>The <code class="xref py py-class docutils literal notranslate"><span class="pre">AbstractEventLoopPolicy</span></code> class is deprecated and305will be removed in Python 3.16.</p>306</div>307</dd></dl>308 309<p id="asyncio-policy-builtin">asyncio ships with the following built-in policies:</p>310<dl class="py class">311<dt class="sig sig-object py" id="asyncio.DefaultEventLoopPolicy">312<em class="property"><span class="k"><span class="pre">class</span></span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">asyncio.</span></span><span class="sig-name descname"><span class="pre">DefaultEventLoopPolicy</span></span><a class="headerlink" href="#asyncio.DefaultEventLoopPolicy" title="Link to this definition">¶</a></dt>313<dd><p>The default asyncio policy.  Uses <a class="reference internal" href="asyncio-eventloop.html#asyncio.SelectorEventLoop" title="asyncio.SelectorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">SelectorEventLoop</span></code></a>314on Unix and <a class="reference internal" href="asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a> on Windows.</p>315<p>There is no need to install the default policy manually. asyncio316is configured to use the default policy automatically.</p>317<div class="versionchanged">318<p><span class="versionmodified changed">Changed in version 3.8: </span>On Windows, <a class="reference internal" href="asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a> is now used by default.</p>319</div>320<div class="versionchanged">321<p><span class="versionmodified changed">Changed in version 3.14: </span>The <a class="reference internal" href="asyncio-eventloop.html#asyncio.get_event_loop" title="asyncio.get_event_loop"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get_event_loop()</span></code></a> method of the default asyncio policy now322raises a <a class="reference internal" href="exceptions.html#RuntimeError" title="RuntimeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">RuntimeError</span></code></a> if there is no set event loop.</p>323</div>324<div class="deprecated">325<p><span class="versionmodified deprecated">Deprecated since version 3.14: </span>The <code class="xref py py-class docutils literal notranslate"><span class="pre">DefaultEventLoopPolicy</span></code> class is deprecated and326will be removed in Python 3.16.</p>327</div>328</dd></dl>329 330<dl class="py class">331<dt class="sig sig-object py" id="asyncio.WindowsSelectorEventLoopPolicy">332<em class="property"><span class="k"><span class="pre">class</span></span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">asyncio.</span></span><span class="sig-name descname"><span class="pre">WindowsSelectorEventLoopPolicy</span></span><a class="headerlink" href="#asyncio.WindowsSelectorEventLoopPolicy" title="Link to this definition">¶</a></dt>333<dd><p>An alternative event loop policy that uses the334<a class="reference internal" href="asyncio-eventloop.html#asyncio.SelectorEventLoop" title="asyncio.SelectorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">SelectorEventLoop</span></code></a> event loop implementation.</p>335<div class="availability docutils container">336<p><a class="reference internal" href="intro.html#availability"><span class="std std-ref">Availability</span></a>: Windows.</p>337</div>338<div class="deprecated">339<p><span class="versionmodified deprecated">Deprecated since version 3.14: </span>The <code class="xref py py-class docutils literal notranslate"><span class="pre">WindowsSelectorEventLoopPolicy</span></code> class is deprecated and340will be removed in Python 3.16.</p>341</div>342</dd></dl>343 344<dl class="py class">345<dt class="sig sig-object py" id="asyncio.WindowsProactorEventLoopPolicy">346<em class="property"><span class="k"><span class="pre">class</span></span><span class="w"> </span></em><span class="sig-prename descclassname"><span class="pre">asyncio.</span></span><span class="sig-name descname"><span class="pre">WindowsProactorEventLoopPolicy</span></span><a class="headerlink" href="#asyncio.WindowsProactorEventLoopPolicy" title="Link to this definition">¶</a></dt>347<dd><p>An alternative event loop policy that uses the348<a class="reference internal" href="asyncio-eventloop.html#asyncio.ProactorEventLoop" title="asyncio.ProactorEventLoop"><code class="xref py py-class docutils literal notranslate"><span class="pre">ProactorEventLoop</span></code></a> event loop implementation.</p>349<div class="availability docutils container">350<p><a class="reference internal" href="intro.html#availability"><span class="std std-ref">Availability</span></a>: Windows.</p>351</div>352<div class="deprecated">353<p><span class="versionmodified deprecated">Deprecated since version 3.14: </span>The <code class="xref py py-class docutils literal notranslate"><span class="pre">WindowsProactorEventLoopPolicy</span></code> class is deprecated and354will be removed in Python 3.16.</p>355</div>356</dd></dl>357 358</section>359<section id="custom-policies">360<span id="asyncio-custom-policies"></span><h2>Custom Policies<a class="headerlink" href="#custom-policies" title="Link to this heading">¶</a></h2>361<p>To implement a new event loop policy, it is recommended to subclass362<a class="reference internal" href="#asyncio.DefaultEventLoopPolicy" title="asyncio.DefaultEventLoopPolicy"><code class="xref py py-class docutils literal notranslate"><span class="pre">DefaultEventLoopPolicy</span></code></a> and override the methods for which363custom behavior is wanted, e.g.:</p>364<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">class</span><span class="w"> </span><span class="nc">MyEventLoopPolicy</span><span class="p">(</span><span class="n">asyncio</span><span class="o">.</span><span class="n">DefaultEventLoopPolicy</span><span class="p">):</span>365 366    <span class="k">def</span><span class="w"> </span><span class="nf">get_event_loop</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>367<span class="w">        </span><span class="sd">&quot;&quot;&quot;Get the event loop.</span>368 369<span class="sd">        This may be None or an instance of EventLoop.</span>370<span class="sd">        &quot;&quot;&quot;</span>371        <span class="n">loop</span> <span class="o">=</span> <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="n">get_event_loop</span><span class="p">()</span>372        <span class="c1"># Do something with loop ...</span>373        <span class="k">return</span> <span class="n">loop</span>374 375<span class="n">asyncio</span><span class="o">.</span><span class="n">set_event_loop_policy</span><span class="p">(</span><span class="n">MyEventLoopPolicy</span><span class="p">())</span>376</pre></div>377</div>378</section>379</section>380 381 382            <div class="clearer"></div>383          </div>384        </div>385      </div>386      <div class="sphinxsidebar" role="navigation" aria-label="Main">387        <div class="sphinxsidebarwrapper">388  <div>389    <h3><a href="../contents.html">Table of Contents</a></h3>390    <ul>391<li><a class="reference internal" href="#">Policies</a><ul>392<li><a class="reference internal" href="#getting-and-setting-the-policy">Getting and Setting the Policy</a></li>393<li><a class="reference internal" href="#policy-objects">Policy Objects</a></li>394<li><a class="reference internal" href="#custom-policies">Custom Policies</a></li>395</ul>396</li>397</ul>398 399  </div>400  <div>401    <h4>Previous topic</h4>402    <p class="topless"><a href="asyncio-protocol.html"403                          title="previous chapter">Transports and Protocols</a></p>404  </div>405  <div>406    <h4>Next topic</h4>407    <p class="topless"><a href="asyncio-platforms.html"408                          title="next chapter">Platform Support</a></p>409  </div>410  <script>411    document.addEventListener('DOMContentLoaded', () => {412        const title = document.querySelector('meta[property="og:title"]').content;413        const elements = document.querySelectorAll('.improvepage');414        const pageurl = window.location.href.split('?')[0];415        elements.forEach(element => {416            const url = new URL(element.href.split('?')[0].replace("-nojs", ""));417            url.searchParams.set('pagetitle', title);418            url.searchParams.set('pageurl', pageurl);419            url.searchParams.set('pagesource', "library/asyncio-policy.rst");420            element.href = url.toString();421        });422    });423  </script>424  <div role="note" aria-label="source link">425    <h3>This page</h3>426    <ul class="this-page-menu">427      <li><a href="../bugs.html">Report a bug</a></li>428      <li><a class="improvepage" href="../improve-page-nojs.html">Improve this page</a></li>429      <li>430        <a href="https://github.com/python/cpython/blob/main/Doc/library/asyncio-policy.rst?plain=1"431            rel="nofollow">Show source432        </a>433      </li>434      435    </ul>436  </div>437        </div>438<div id="sidebarbutton" title="Collapse sidebar">439<span>«</span>440</div>441 442      </div>443      <div class="clearer"></div>444    </div>  445    <div class="related" role="navigation" aria-label="Related">446      <h3>Navigation</h3>447      <ul>448        <li class="right" style="margin-right: 10px">449          <a href="../genindex.html" title="General Index"450             >index</a></li>451        <li class="right" >452          <a href="../py-modindex.html" title="Python Module Index"453             >modules</a> |</li>454        <li class="right" >455          <a href="asyncio-platforms.html" title="Platform Support"456             >next</a> |</li>457        <li class="right" >458          <a href="asyncio-protocol.html" title="Transports and Protocols"459             >previous</a> |</li>460 461          <li><img src="../_static/py.svg" alt="Python logo" style="vertical-align: middle; margin-top: -1px"></li>462          <li><a href="https://www.python.org/">Python</a> &#187;</li>463          <li class="switchers">464            <div class="language_switcher_placeholder"></div>465            <div class="version_switcher_placeholder"></div>466          </li>467          <li>468              469          </li>470    <li id="cpython-language-and-version">471      <a href="../index.html">3.15.0a6 Documentation</a> &#187;472    </li>473 474          <li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> &#187;</li>475          <li class="nav-item nav-item-2"><a href="ipc.html" >Networking and Interprocess Communication</a> &#187;</li>476          <li class="nav-item nav-item-3"><a href="asyncio.html" ><code class="xref py py-mod docutils literal notranslate"><span class="pre">asyncio</span></code> — Asynchronous I/O</a> &#187;</li>477        <li class="nav-item nav-item-this"><a href="">Policies</a></li>478                <li class="right">479                    480 481    <div class="inline-search" role="search">482        <form class="inline-search" action="../search.html" method="get">483          <input placeholder="Quick search" aria-label="Quick search" type="search" name="q" id="search-box">484          <input type="submit" value="Go">485        </form>486    </div>487                     |488                </li>489            <li class="right">490<label class="theme-selector-label">491    Theme492    <select class="theme-selector" oninput="activateTheme(this.value)">493        <option value="auto" selected>Auto</option>494        <option value="light">Light</option>495        <option value="dark">Dark</option>496    </select>497</label> |</li>498            499      </ul>500    </div>  501    <div class="footer">502    &copy; <a href="../copyright.html">Copyright</a> 2001 Python Software Foundation.503    <br>504    This page is licensed under the Python Software Foundation License Version 2.505    <br>506    Examples, recipes, and other code in the documentation are additionally licensed under the Zero Clause BSD License.507    <br>508    509      See <a href="/license.html">History and License</a> for more information.<br>510    511    512    <br>513 514    The Python Software Foundation is a non-profit corporation.515<a href="https://www.python.org/psf/donations/">Please donate.</a>516<br>517    <br>518      Last updated on Mar 10, 2026 (08:58 UTC).519    520      <a href="/bugs.html">Found a bug</a>?521    522    <br>523 524    Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 8.2.3.525    </div>526 527  </body>528</html>