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I/O</a> »</li> <li class="right"> <div class="inline-search" style="display: none" role="search"> <form class="inline-search" action="../search.html" method="get"> <input placeholder="Quick search" type="text" name="q" /> <input type="submit" value="Go" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> <script type="text/javascript">$('.inline-search').show(0);</script> | </li> </ul> </div> <div class="document"> <div class="documentwrapper"> <div class="bodywrapper"> <div class="body" role="main"> <div class="section" id="futures"> <span id="asyncio-futures"></span><h1>Futures<a class="headerlink" href="#futures" title="Permalink to this headline">¶</a></h1> <p><em>Future</em> objects are used to bridge <strong>low-level callback-based code</strong> with high-level async/await code.</p> <div class="section" id="future-functions"> <h2>Future Functions<a class="headerlink" href="#future-functions" title="Permalink to this headline">¶</a></h2> <dl class="function"> <dt id="asyncio.isfuture"> <code class="descclassname">asyncio.</code><code class="descname">isfuture</code><span class="sig-paren">(</span><em>obj</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.isfuture" title="Permalink to this definition">¶</a></dt> <dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if <em>obj</em> is either of:</p> <ul class="simple"> <li><p>an instance of <a class="reference internal" href="#asyncio.Future" title="asyncio.Future"><code class="xref py py-class docutils literal notranslate"><span class="pre">asyncio.Future</span></code></a>,</p></li> <li><p>an instance of <a class="reference internal" href="asyncio-task.html#asyncio.Task" title="asyncio.Task"><code class="xref py py-class docutils literal notranslate"><span class="pre">asyncio.Task</span></code></a>,</p></li> <li><p>a Future-like object with a <code class="docutils literal notranslate"><span class="pre">_asyncio_future_blocking</span></code> attribute.</p></li> </ul> <div class="versionadded"> <p><span class="versionmodified added">New in version 3.5.</span></p> </div> </dd></dl> <dl class="function"> <dt id="asyncio.ensure_future"> <code class="descclassname">asyncio.</code><code class="descname">ensure_future</code><span class="sig-paren">(</span><em>obj</em>, <em>*</em>, <em>loop=None</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.ensure_future" title="Permalink to this definition">¶</a></dt> <dd><p>Return:</p> <ul class="simple"> <li><p><em>obj</em> argument as is, if <em>obj</em> is a <a class="reference internal" href="#asyncio.Future" title="asyncio.Future"><code class="xref py py-class docutils literal notranslate"><span class="pre">Future</span></code></a>, a <a class="reference internal" href="asyncio-task.html#asyncio.Task" title="asyncio.Task"><code class="xref py py-class docutils literal notranslate"><span class="pre">Task</span></code></a>, or a Future-like object (<a class="reference internal" href="#asyncio.isfuture" title="asyncio.isfuture"><code class="xref py py-func docutils literal notranslate"><span class="pre">isfuture()</span></code></a> is used for the test.)</p></li> <li><p>a <a class="reference internal" href="asyncio-task.html#asyncio.Task" title="asyncio.Task"><code class="xref py py-class docutils literal notranslate"><span class="pre">Task</span></code></a> object wrapping <em>obj</em>, if <em>obj</em> is a coroutine (<a class="reference internal" href="asyncio-task.html#asyncio.iscoroutine" title="asyncio.iscoroutine"><code class="xref py py-func docutils literal notranslate"><span class="pre">iscoroutine()</span></code></a> is used for the test.)</p></li> <li><p>a <a class="reference internal" href="asyncio-task.html#asyncio.Task" title="asyncio.Task"><code class="xref py py-class docutils literal notranslate"><span class="pre">Task</span></code></a> object that would await on <em>obj</em>, if <em>obj</em> is an awaitable (<a class="reference internal" href="inspect.html#inspect.isawaitable" title="inspect.isawaitable"><code class="xref py py-func docutils literal notranslate"><span class="pre">inspect.isawaitable()</span></code></a> is used for the test.)</p></li> </ul> <p>If <em>obj</em> is neither of the above a <a class="reference internal" href="exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> is raised.</p> <div class="admonition important"> <p class="admonition-title">Important</p> <p>See also the <a class="reference internal" href="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> function which is the preferred way for creating new Tasks.</p> </div> <div class="versionchanged"> <p><span class="versionmodified changed">Changed in version 3.5.1: </span>The function accepts any <a class="reference internal" href="../glossary.html#term-awaitable"><span class="xref std std-term">awaitable</span></a> object.</p> </div> </dd></dl> <dl class="function"> <dt id="asyncio.wrap_future"> <code class="descclassname">asyncio.</code><code class="descname">wrap_future</code><span class="sig-paren">(</span><em>future</em>, <em>*</em>, <em>loop=None</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.wrap_future" title="Permalink to this definition">¶</a></dt> <dd><p>Wrap a <a class="reference internal" href="concurrent.futures.html#concurrent.futures.Future" title="concurrent.futures.Future"><code class="xref py py-class docutils literal notranslate"><span class="pre">concurrent.futures.Future</span></code></a> object in a <a class="reference internal" href="#asyncio.Future" title="asyncio.Future"><code class="xref py py-class docutils literal notranslate"><span class="pre">asyncio.Future</span></code></a> object.</p> </dd></dl> </div> <div class="section" id="future-object"> <h2>Future Object<a class="headerlink" href="#future-object" title="Permalink to this headline">¶</a></h2> <dl class="class"> <dt id="asyncio.Future"> <em class="property">class </em><code class="descclassname">asyncio.</code><code class="descname">Future</code><span class="sig-paren">(</span><em>*</em>, <em>loop=None</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future" title="Permalink to this definition">¶</a></dt> <dd><p>A Future represents an eventual result of an asynchronous operation. Not thread-safe.</p> <p>Future is an <a class="reference internal" href="../glossary.html#term-awaitable"><span class="xref std std-term">awaitable</span></a> object. Coroutines can await on Future objects until they either have a result or an exception set, or until they are cancelled.</p> <p>Typically Futures are used to enable low-level callback-based code (e.g. in protocols implemented using asyncio <a class="reference internal" href="asyncio-protocol.html#asyncio-transports-protocols"><span class="std std-ref">transports</span></a>) to interoperate with high-level async/await code.</p> <p>The rule of thumb is to never expose Future objects in user-facing APIs, and the recommended way to create a Future object is to call <a class="reference internal" href="asyncio-eventloop.html#asyncio.loop.create_future" title="asyncio.loop.create_future"><code class="xref py py-meth docutils literal notranslate"><span class="pre">loop.create_future()</span></code></a>. This way alternative event loop implementations can inject their own optimized implementations of a Future object.</p> <div class="versionchanged"> <p><span class="versionmodified changed">Changed in version 3.7: </span>Added support for the <a class="reference internal" href="contextvars.html#module-contextvars" title="contextvars: Context Variables"><code class="xref py py-mod docutils literal notranslate"><span class="pre">contextvars</span></code></a> module.</p> </div> <dl class="method"> <dt id="asyncio.Future.result"> <code class="descname">result</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.result" title="Permalink to this definition">¶</a></dt> <dd><p>Return the result of the Future.</p> <p>If the Future is <em>done</em> and has a result set by the <a class="reference internal" href="#asyncio.Future.set_result" title="asyncio.Future.set_result"><code class="xref py py-meth docutils literal notranslate"><span class="pre">set_result()</span></code></a> method, the result value is returned.</p> <p>If the Future is <em>done</em> and has an exception set by the <a class="reference internal" href="#asyncio.Future.set_exception" title="asyncio.Future.set_exception"><code class="xref py py-meth docutils literal notranslate"><span class="pre">set_exception()</span></code></a> method, this method raises the exception.</p> <p>If the Future has been <em>cancelled</em>, this method raises a <a class="reference internal" href="asyncio-exceptions.html#asyncio.CancelledError" title="asyncio.CancelledError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">CancelledError</span></code></a> exception.</p> <p>If the Future’s result isn’t yet available, this method raises a <a class="reference internal" href="asyncio-exceptions.html#asyncio.InvalidStateError" title="asyncio.InvalidStateError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">InvalidStateError</span></code></a> exception.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.set_result"> <code class="descname">set_result</code><span class="sig-paren">(</span><em>result</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.set_result" title="Permalink to this definition">¶</a></dt> <dd><p>Mark the Future as <em>done</em> and set its result.</p> <p>Raises a <a class="reference internal" href="asyncio-exceptions.html#asyncio.InvalidStateError" title="asyncio.InvalidStateError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">InvalidStateError</span></code></a> error if the Future is already <em>done</em>.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.set_exception"> <code class="descname">set_exception</code><span class="sig-paren">(</span><em>exception</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.set_exception" title="Permalink to this definition">¶</a></dt> <dd><p>Mark the Future as <em>done</em> and set an exception.</p> <p>Raises a <a class="reference internal" href="asyncio-exceptions.html#asyncio.InvalidStateError" title="asyncio.InvalidStateError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">InvalidStateError</span></code></a> error if the Future is already <em>done</em>.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.done"> <code class="descname">done</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.done" title="Permalink to this definition">¶</a></dt> <dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the Future is <em>done</em>.</p> <p>A Future is <em>done</em> if it was <em>cancelled</em> or if it has a result or an exception set with <a class="reference internal" href="#asyncio.Future.set_result" title="asyncio.Future.set_result"><code class="xref py py-meth docutils literal notranslate"><span class="pre">set_result()</span></code></a> or <a class="reference internal" href="#asyncio.Future.set_exception" title="asyncio.Future.set_exception"><code class="xref py py-meth docutils literal notranslate"><span class="pre">set_exception()</span></code></a> calls.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.cancelled"> <code class="descname">cancelled</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.cancelled" title="Permalink to this definition">¶</a></dt> <dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the Future was <em>cancelled</em>.</p> <p>The method is usually used to check if a Future is not <em>cancelled</em> before setting a result or an exception for it:</p> <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">if</span> <span class="ow">not</span> <span class="n">fut</span><span class="o">.</span><span class="n">cancelled</span><span class="p">():</span> <span class="n">fut</span><span class="o">.</span><span class="n">set_result</span><span class="p">(</span><span class="mi">42</span><span class="p">)</span> </pre></div> </div> </dd></dl> <dl class="method"> <dt id="asyncio.Future.add_done_callback"> <code class="descname">add_done_callback</code><span class="sig-paren">(</span><em>callback</em>, <em>*</em>, <em>context=None</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.add_done_callback" title="Permalink to this definition">¶</a></dt> <dd><p>Add a callback to be run when the Future is <em>done</em>.</p> <p>The <em>callback</em> is called with the Future object as its only argument.</p> <p>If the Future is already <em>done</em> when this method is called, the callback is scheduled with <a class="reference internal" href="asyncio-eventloop.html#asyncio.loop.call_soon" title="asyncio.loop.call_soon"><code class="xref py py-meth docutils literal notranslate"><span class="pre">loop.call_soon()</span></code></a>.</p> <p>An optional keyword-only <em>context</em> argument allows specifying a custom <a class="reference internal" href="contextvars.html#contextvars.Context" title="contextvars.Context"><code class="xref py py-class docutils literal notranslate"><span class="pre">contextvars.Context</span></code></a> for the <em>callback</em> to run in. The current context is used when no <em>context</em> is provided.</p> <p><a class="reference internal" href="functools.html#functools.partial" title="functools.partial"><code class="xref py py-func docutils literal notranslate"><span class="pre">functools.partial()</span></code></a> can be used to pass parameters to the callback, e.g.:</p> <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="c1"># Call 'print("Future:", fut)' when "fut" is done.</span> <span class="n">fut</span><span class="o">.</span><span class="n">add_done_callback</span><span class="p">(</span> <span class="n">functools</span><span class="o">.</span><span class="n">partial</span><span class="p">(</span><span class="nb">print</span><span class="p">,</span> <span class="s2">"Future:"</span><span class="p">))</span> </pre></div> </div> <div class="versionchanged"> <p><span class="versionmodified changed">Changed in version 3.7: </span>The <em>context</em> keyword-only parameter was added. See <span class="target" id="index-0"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0567"><strong>PEP 567</strong></a> for more details.</p> </div> </dd></dl> <dl class="method"> <dt id="asyncio.Future.remove_done_callback"> <code class="descname">remove_done_callback</code><span class="sig-paren">(</span><em>callback</em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.remove_done_callback" title="Permalink to this definition">¶</a></dt> <dd><p>Remove <em>callback</em> from the callbacks list.</p> <p>Returns the number of callbacks removed, which is typically 1, unless a callback was added more than once.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.cancel"> <code class="descname">cancel</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.cancel" title="Permalink to this definition">¶</a></dt> <dd><p>Cancel the Future and schedule callbacks.</p> <p>If the Future is already <em>done</em> or <em>cancelled</em>, return <code class="docutils literal notranslate"><span class="pre">False</span></code>. Otherwise, change the Future’s state to <em>cancelled</em>, schedule the callbacks, and return <code class="docutils literal notranslate"><span class="pre">True</span></code>.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.exception"> <code class="descname">exception</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.exception" title="Permalink to this definition">¶</a></dt> <dd><p>Return the exception that was set on this Future.</p> <p>The exception (or <code class="docutils literal notranslate"><span class="pre">None</span></code> if no exception was set) is returned only if the Future is <em>done</em>.</p> <p>If the Future has been <em>cancelled</em>, this method raises a <a class="reference internal" href="asyncio-exceptions.html#asyncio.CancelledError" title="asyncio.CancelledError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">CancelledError</span></code></a> exception.</p> <p>If the Future isn’t <em>done</em> yet, this method raises an <a class="reference internal" href="asyncio-exceptions.html#asyncio.InvalidStateError" title="asyncio.InvalidStateError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">InvalidStateError</span></code></a> exception.</p> </dd></dl> <dl class="method"> <dt id="asyncio.Future.get_loop"> <code class="descname">get_loop</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Future.get_loop" title="Permalink to this definition">¶</a></dt> <dd><p>Return the event loop the Future object is bound to.</p> <div class="versionadded"> <p><span class="versionmodified added">New in version 3.7.</span></p> </div> </dd></dl> </dd></dl> <p id="asyncio-example-future">This example creates a Future object, creates and schedules an asynchronous Task to set result for the Future, and waits until the Future has a result:</p> <div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">async</span> <span class="k">def</span> <span class="nf">set_after</span><span class="p">(</span><span class="n">fut</span><span class="p">,</span> <span class="n">delay</span><span class="p">,</span> <span class="n">value</span><span class="p">):</span> <span class="c1"># Sleep for *delay* seconds.</span> <span class="k">await</span> <span class="n">asyncio</span><span class="o">.</span><span class="n">sleep</span><span class="p">(</span><span class="n">delay</span><span class="p">)</span> <span class="c1"># Set *value* as a result of *fut* Future.</span> <span class="n">fut</span><span class="o">.</span><span class="n">set_result</span><span class="p">(</span><span class="n">value</span><span class="p">)</span> <span class="k">async</span> <span class="k">def</span> <span class="nf">main</span><span class="p">():</span> <span class="c1"># Get the current event loop.</span> <span class="n">loop</span> <span class="o">=</span> <span class="n">asyncio</span><span class="o">.</span><span class="n">get_running_loop</span><span class="p">()</span> <span class="c1"># Create a new Future object.</span> <span class="n">fut</span> <span class="o">=</span> <span class="n">loop</span><span class="o">.</span><span class="n">create_future</span><span class="p">()</span> <span class="c1"># Run "set_after()" coroutine in a parallel Task.</span> <span class="c1"># We are using the low-level "loop.create_task()" API here because</span> <span class="c1"># we already have a reference to the event loop at hand.</span> <span class="c1"># Otherwise we could have just used "asyncio.create_task()".</span> <span class="n">loop</span><span class="o">.</span><span class="n">create_task</span><span class="p">(</span> <span class="n">set_after</span><span class="p">(</span><span class="n">fut</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="s1">'... world'</span><span class="p">))</span> <span class="nb">print</span><span class="p">(</span><span class="s1">'hello ...'</span><span class="p">)</span> <span class="c1"># Wait until *fut* has a result (1 second) and print it.</span> <span class="nb">print</span><span class="p">(</span><span class="k">await</span> <span class="n">fut</span><span class="p">)</span> <span class="n">asyncio</span><span class="o">.</span><span class="n">run</span><span class="p">(</span><span class="n">main</span><span class="p">())</span> </pre></div> </div> <div class="admonition important"> <p class="admonition-title">Important</p> <p>The Future object was designed to mimic <a class="reference internal" href="concurrent.futures.html#concurrent.futures.Future" title="concurrent.futures.Future"><code class="xref py py-class docutils literal notranslate"><span class="pre">concurrent.futures.Future</span></code></a>. Key differences include:</p> <ul class="simple"> <li><p>unlike asyncio Futures, <a class="reference internal" href="concurrent.futures.html#concurrent.futures.Future" title="concurrent.futures.Future"><code class="xref py py-class docutils literal notranslate"><span class="pre">concurrent.futures.Future</span></code></a> instances cannot be awaited.</p></li> <li><p><a class="reference internal" href="#asyncio.Future.result" title="asyncio.Future.result"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.Future.result()</span></code></a> and <a class="reference internal" href="#asyncio.Future.exception" title="asyncio.Future.exception"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.Future.exception()</span></code></a> do not accept the <em>timeout</em> argument.</p></li> <li><p><a class="reference internal" href="#asyncio.Future.result" title="asyncio.Future.result"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.Future.result()</span></code></a> and <a class="reference internal" href="#asyncio.Future.exception" title="asyncio.Future.exception"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.Future.exception()</span></code></a> raise an <a class="reference internal" href="asyncio-exceptions.html#asyncio.InvalidStateError" title="asyncio.InvalidStateError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">InvalidStateError</span></code></a> exception when the Future is not <em>done</em>.</p></li> <li><p>Callbacks registered with <a class="reference internal" href="#asyncio.Future.add_done_callback" title="asyncio.Future.add_done_callback"><code class="xref py py-meth docutils literal notranslate"><span class="pre">asyncio.Future.add_done_callback()</span></code></a> are not called immediately. They are scheduled with <a class="reference internal" href="asyncio-eventloop.html#asyncio.loop.call_soon" title="asyncio.loop.call_soon"><code class="xref py py-meth docutils literal notranslate"><span class="pre">loop.call_soon()</span></code></a> instead.</p></li> <li><p>asyncio Future is not compatible with the <a class="reference internal" href="concurrent.futures.html#concurrent.futures.wait" title="concurrent.futures.wait"><code class="xref py py-func docutils literal notranslate"><span class="pre">concurrent.futures.wait()</span></code></a> and <a class="reference internal" href="concurrent.futures.html#concurrent.futures.as_completed" title="concurrent.futures.as_completed"><code class="xref py py-func docutils literal notranslate"><span class="pre">concurrent.futures.as_completed()</span></code></a> functions.</p></li> </ul> </div> </div> </div> </div> </div> </div> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h3><a href="../contents.html">Table of Contents</a></h3> <ul> <li><a class="reference internal" href="#">Futures</a><ul> <li><a class="reference internal" href="#future-functions">Future Functions</a></li> <li><a class="reference internal" href="#future-object">Future Object</a></li> </ul> </li> </ul> <h4>Previous topic</h4> <p class="topless"><a href="asyncio-eventloop.html" title="previous chapter">Event Loop</a></p> <h4>Next topic</h4> <p class="topless"><a href="asyncio-protocol.html" title="next chapter">Transports and Protocols</a></p> <div role="note" aria-label="source link"> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li> <a href="https://github.com/python/cpython/blob/3.7/Doc/library/asyncio-future.rst" rel="nofollow">Show Source </a> </li> </ul> </div> </div> </div> <div class="clearer"></div> </div> <div class="related" role="navigation" aria-label="related navigation"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="asyncio-protocol.html" title="Transports and Protocols" >next</a> |</li> <li class="right" > <a href="asyncio-eventloop.html" title="Event Loop" >previous</a> |</li> <li><img src="../_static/py.png" alt="" style="vertical-align: middle; margin-top: -1px"/></li> <li><a href="https://www.python.org/">Python</a> »</li> <li> <span class="language_switcher_placeholder">en</span> <span class="version_switcher_placeholder">3.7.4</span> <a href="../index.html">Documentation </a> » </li> <li class="nav-item nav-item-1"><a href="index.html" >The Python Standard Library</a> »</li> <li class="nav-item nav-item-2"><a href="ipc.html" >Networking and Interprocess Communication</a> »</li> <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> »</li> <li class="right"> <div class="inline-search" style="display: none" role="search"> <form class="inline-search" action="../search.html" method="get"> <input placeholder="Quick search" type="text" name="q" /> <input type="submit" value="Go" /> <input type="hidden" name="check_keywords" value="yes" /> <input type="hidden" name="area" value="default" /> </form> </div> <script type="text/javascript">$('.inline-search').show(0);</script> | </li> </ul> </div> <div class="footer"> © <a href="../copyright.html">Copyright</a> 2001-2019, Python Software Foundation. <br /> The Python Software Foundation is a non-profit corporation. <a href="https://www.python.org/psf/donations/">Please donate.</a> <br /> Last updated on Jul 13, 2019. <a href="../bugs.html">Found a bug</a>? <br /> Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 2.0.1. </div> </body> </html>