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<section id="queues">
<span id="asyncio-queues"></span><h1>Queues<a class="headerlink" href="#queues" title="Link to this heading"></a></h1>
<p><strong>Source code:</strong> <a class="extlink-source reference external" href="https://github.com/python/cpython/tree/main/Lib/asyncio/queues.py">Lib/asyncio/queues.py</a></p>
<hr class="docutils" />
<p>asyncio queues are designed to be similar to classes of the
<a class="reference internal" href="queue.html#module-queue" title="queue: A synchronized queue class."><code class="xref py py-mod docutils literal notranslate"><span class="pre">queue</span></code></a> module. Although asyncio queues are not thread-safe,
they are designed to be used specifically in async/await code.</p>
<p>Note that methods of asyncio queues don’t have a <em>timeout</em> parameter;
use <a class="reference internal" href="asyncio-task.html#asyncio.wait_for" title="asyncio.wait_for"><code class="xref py py-func docutils literal notranslate"><span class="pre">asyncio.wait_for()</span></code></a> function to do queue operations with a
timeout.</p>
<p>See also the <a class="reference internal" href="#examples">Examples</a> section below.</p>
<section id="queue">
<h2>Queue<a class="headerlink" href="#queue" title="Link to this heading"></a></h2>
<dl class="py class">
<dt class="sig sig-object py" id="asyncio.Queue">
<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">Queue</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">maxsize</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">0</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue" title="Link to this definition"></a></dt>
<dd><p>A first in, first out (FIFO) queue.</p>
<p>If <em>maxsize</em> is less than or equal to zero, the queue size is
infinite. If it is an integer greater than <code class="docutils literal notranslate"><span class="pre">0</span></code>, then
<code class="docutils literal notranslate"><span class="pre">await</span> <span class="pre">put()</span></code> blocks when the queue reaches <em>maxsize</em>
until an item is removed by <a class="reference internal" href="#asyncio.Queue.get" title="asyncio.Queue.get"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get()</span></code></a>.</p>
<p>Unlike the standard library threading <a class="reference internal" href="queue.html#module-queue" title="queue: A synchronized queue class."><code class="xref py py-mod docutils literal notranslate"><span class="pre">queue</span></code></a>, the size of
the queue is always known and can be returned by calling the
<a class="reference internal" href="#asyncio.Queue.qsize" title="asyncio.Queue.qsize"><code class="xref py py-meth docutils literal notranslate"><span class="pre">qsize()</span></code></a> method.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.10: </span>Removed the <em>loop</em> parameter.</p>
</div>
<p>This class is <a class="reference internal" href="asyncio-dev.html#asyncio-multithreading"><span class="std std-ref">not thread safe</span></a>.</p>
<dl class="py attribute">
<dt class="sig sig-object py" id="asyncio.Queue.maxsize">
<span class="sig-name descname"><span class="pre">maxsize</span></span><a class="headerlink" href="#asyncio.Queue.maxsize" title="Link to this definition"></a></dt>
<dd><p>Number of items allowed in the queue.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.empty">
<span class="sig-name descname"><span class="pre">empty</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.empty" title="Link to this definition"></a></dt>
<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the queue is empty, <code class="docutils literal notranslate"><span class="pre">False</span></code> otherwise.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.full">
<span class="sig-name descname"><span class="pre">full</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.full" title="Link to this definition"></a></dt>
<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if there are <a class="reference internal" href="#asyncio.Queue.maxsize" title="asyncio.Queue.maxsize"><code class="xref py py-attr docutils literal notranslate"><span class="pre">maxsize</span></code></a> items in the queue.</p>
<p>If the queue was initialized with <code class="docutils literal notranslate"><span class="pre">maxsize=0</span></code> (the default),
then <code class="xref py py-meth docutils literal notranslate"><span class="pre">full()</span></code> never returns <code class="docutils literal notranslate"><span class="pre">True</span></code>.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.get">
<em class="property"><span class="k"><span class="pre">async</span></span><span class="w"> </span></em><span class="sig-name descname"><span class="pre">get</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.get" title="Link to this definition"></a></dt>
<dd><p>Remove and return an item from the queue. If queue is empty,
wait until an item is available.</p>
<p>Raises <a class="reference internal" href="#asyncio.QueueShutDown" title="asyncio.QueueShutDown"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueShutDown</span></code></a> if the queue has been shut down and
is empty, or if the queue has been shut down immediately.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.get_nowait">
<span class="sig-name descname"><span class="pre">get_nowait</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.get_nowait" title="Link to this definition"></a></dt>
<dd><p>Return an item if one is immediately available, else raise
<a class="reference internal" href="#asyncio.QueueEmpty" title="asyncio.QueueEmpty"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueEmpty</span></code></a>.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.join">
<em class="property"><span class="k"><span class="pre">async</span></span><span class="w"> </span></em><span class="sig-name descname"><span class="pre">join</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.join" title="Link to this definition"></a></dt>
<dd><p>Block until all items in the queue have been received and processed.</p>
<p>The count of unfinished tasks goes up whenever an item is added
to the queue. The count goes down whenever a consumer coroutine calls
<a class="reference internal" href="#asyncio.Queue.task_done" title="asyncio.Queue.task_done"><code class="xref py py-meth docutils literal notranslate"><span class="pre">task_done()</span></code></a> to indicate that the item was retrieved and all
work on it is complete. When the count of unfinished tasks drops
to zero, <code class="xref py py-meth docutils literal notranslate"><span class="pre">join()</span></code> unblocks.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.put">
<em class="property"><span class="k"><span class="pre">async</span></span><span class="w"> </span></em><span class="sig-name descname"><span class="pre">put</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">item</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.put" title="Link to this definition"></a></dt>
<dd><p>Put an item into the queue. If the queue is full, wait until a
free slot is available before adding the item.</p>
<p>Raises <a class="reference internal" href="#asyncio.QueueShutDown" title="asyncio.QueueShutDown"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueShutDown</span></code></a> if the queue has been shut down.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.put_nowait">
<span class="sig-name descname"><span class="pre">put_nowait</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">item</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.put_nowait" title="Link to this definition"></a></dt>
<dd><p>Put an item into the queue without blocking.</p>
<p>If no free slot is immediately available, raise <a class="reference internal" href="#asyncio.QueueFull" title="asyncio.QueueFull"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueFull</span></code></a>.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.qsize">
<span class="sig-name descname"><span class="pre">qsize</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.qsize" title="Link to this definition"></a></dt>
<dd><p>Return the number of items in the queue.</p>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.shutdown">
<span class="sig-name descname"><span class="pre">shutdown</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">immediate</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">False</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.shutdown" title="Link to this definition"></a></dt>
<dd><p>Put a <code class="xref py py-class docutils literal notranslate"><span class="pre">Queue</span></code> instance into a shutdown mode.</p>
<p>The queue can no longer grow.
Future calls to <a class="reference internal" href="#asyncio.Queue.put" title="asyncio.Queue.put"><code class="xref py py-meth docutils literal notranslate"><span class="pre">put()</span></code></a> raise <a class="reference internal" href="#asyncio.QueueShutDown" title="asyncio.QueueShutDown"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueShutDown</span></code></a>.
Currently blocked callers of <code class="xref py py-meth docutils literal notranslate"><span class="pre">put()</span></code> will be unblocked
and will raise <code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueShutDown</span></code> in the formerly awaiting task.</p>
<p>If <em>immediate</em> is false (the default), the queue can be wound
down normally with <a class="reference internal" href="#asyncio.Queue.get" title="asyncio.Queue.get"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get()</span></code></a> calls to extract tasks
that have already been loaded.</p>
<p>And if <a class="reference internal" href="#asyncio.Queue.task_done" title="asyncio.Queue.task_done"><code class="xref py py-meth docutils literal notranslate"><span class="pre">task_done()</span></code></a> is called for each remaining task, a
pending <a class="reference internal" href="#asyncio.Queue.join" title="asyncio.Queue.join"><code class="xref py py-meth docutils literal notranslate"><span class="pre">join()</span></code></a> will be unblocked normally.</p>
<p>Once the queue is empty, future calls to <a class="reference internal" href="#asyncio.Queue.get" title="asyncio.Queue.get"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get()</span></code></a> will
raise <a class="reference internal" href="#asyncio.QueueShutDown" title="asyncio.QueueShutDown"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueShutDown</span></code></a>.</p>
<p>If <em>immediate</em> is true, the queue is terminated immediately.
The queue is drained to be completely empty and the count
of unfinished tasks is reduced by the number of tasks drained.
If unfinished tasks is zero, callers of <a class="reference internal" href="#asyncio.Queue.join" title="asyncio.Queue.join"><code class="xref py py-meth docutils literal notranslate"><span class="pre">join()</span></code></a>
are unblocked. Also, blocked callers of <a class="reference internal" href="#asyncio.Queue.get" title="asyncio.Queue.get"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get()</span></code></a>
are unblocked and will raise <a class="reference internal" href="#asyncio.QueueShutDown" title="asyncio.QueueShutDown"><code class="xref py py-exc docutils literal notranslate"><span class="pre">QueueShutDown</span></code></a> because the
queue is empty.</p>
<p>Use caution when using <a class="reference internal" href="#asyncio.Queue.join" title="asyncio.Queue.join"><code class="xref py py-meth docutils literal notranslate"><span class="pre">join()</span></code></a> with <em>immediate</em> set
to true. This unblocks the join even when no work has been done
on the tasks, violating the usual invariant for joining a queue.</p>
<div class="versionadded">
<p><span class="versionmodified added">Added in version 3.13.</span></p>
</div>
</dd></dl>
<dl class="py method">
<dt class="sig sig-object py" id="asyncio.Queue.task_done">
<span class="sig-name descname"><span class="pre">task_done</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#asyncio.Queue.task_done" title="Link to this definition"></a></dt>
<dd><p>Indicate that a formerly enqueued work item is complete.</p>
<p>Used by queue consumers. For each <a class="reference internal" href="#asyncio.Queue.get" title="asyncio.Queue.get"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get()</span></code></a> used to
fetch a work item, a subsequent call to <code class="xref py py-meth docutils literal notranslate"><span class="pre">task_done()</span></code> tells the
queue that the processing on the work item is complete.</p>
<p>If a <a class="reference internal" href="#asyncio.Queue.join" title="asyncio.Queue.join"><code class="xref py py-meth docutils literal notranslate"><span class="pre">join()</span></code></a> is currently blocking, it will resume when all
items have been processed (meaning that a <code class="xref py py-meth docutils literal notranslate"><span class="pre">task_done()</span></code>
call was received for every item that had been <a class="reference internal" href="#asyncio.Queue.put" title="asyncio.Queue.put"><code class="xref py py-meth docutils literal notranslate"><span class="pre">put()</span></code></a>
into the queue).</p>
<p>Raises <a class="reference internal" href="exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> if called more times than there were
items placed in the queue.</p>
</dd></dl>
</dd></dl>
</section>
<section id="priority-queue">
<h2>Priority Queue<a class="headerlink" href="#priority-queue" title="Link to this heading"></a></h2>
<dl class="py class">
<dt class="sig sig-object py" id="asyncio.PriorityQueue">
<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">PriorityQueue</span></span><a class="headerlink" href="#asyncio.PriorityQueue" title="Link to this definition"></a></dt>
<dd><p>A variant of <a class="reference internal" href="#asyncio.Queue" title="asyncio.Queue"><code class="xref py py-class docutils literal notranslate"><span class="pre">Queue</span></code></a>; retrieves entries in priority order
(lowest first).</p>
<p>Entries are typically tuples of the form
<code class="docutils literal notranslate"><span class="pre">(priority_number,</span> <span class="pre">data)</span></code>.</p>
</dd></dl>
</section>
<section id="lifo-queue">
<h2>LIFO Queue<a class="headerlink" href="#lifo-queue" title="Link to this heading"></a></h2>
<dl class="py class">
<dt class="sig sig-object py" id="asyncio.LifoQueue">
<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">LifoQueue</span></span><a class="headerlink" href="#asyncio.LifoQueue" title="Link to this definition"></a></dt>
<dd><p>A variant of <a class="reference internal" href="#asyncio.Queue" title="asyncio.Queue"><code class="xref py py-class docutils literal notranslate"><span class="pre">Queue</span></code></a> that retrieves most recently added
entries first (last in, first out).</p>
</dd></dl>
</section>
<section id="exceptions">
<h2>Exceptions<a class="headerlink" href="#exceptions" title="Link to this heading"></a></h2>
<dl class="py exception">
<dt class="sig sig-object py" id="asyncio.QueueEmpty">
<em class="property"><span class="k"><span class="pre">exception</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">QueueEmpty</span></span><a class="headerlink" href="#asyncio.QueueEmpty" title="Link to this definition"></a></dt>
<dd><p>This exception is raised when the <a class="reference internal" href="#asyncio.Queue.get_nowait" title="asyncio.Queue.get_nowait"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get_nowait()</span></code></a> method
is called on an empty queue.</p>
</dd></dl>
<dl class="py exception">
<dt class="sig sig-object py" id="asyncio.QueueFull">
<em class="property"><span class="k"><span class="pre">exception</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">QueueFull</span></span><a class="headerlink" href="#asyncio.QueueFull" title="Link to this definition"></a></dt>
<dd><p>Exception raised when the <a class="reference internal" href="#asyncio.Queue.put_nowait" title="asyncio.Queue.put_nowait"><code class="xref py py-meth docutils literal notranslate"><span class="pre">put_nowait()</span></code></a> method is called
on a queue that has reached its <em>maxsize</em>.</p>
</dd></dl>
<dl class="py exception">
<dt class="sig sig-object py" id="asyncio.QueueShutDown">
<em class="property"><span class="k"><span class="pre">exception</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">QueueShutDown</span></span><a class="headerlink" href="#asyncio.QueueShutDown" title="Link to this definition"></a></dt>
<dd><p>Exception raised when <a class="reference internal" href="#asyncio.Queue.put" title="asyncio.Queue.put"><code class="xref py py-meth docutils literal notranslate"><span class="pre">put()</span></code></a> or <a class="reference internal" href="#asyncio.Queue.get" title="asyncio.Queue.get"><code class="xref py py-meth docutils literal notranslate"><span class="pre">get()</span></code></a> is
called on a queue which has been shut down.</p>
<div class="versionadded">
<p><span class="versionmodified added">Added in version 3.13.</span></p>
</div>
</dd></dl>
</section>
<section id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
<p id="asyncio-example-queue-dist">Queues can be used to distribute workload between several
concurrent tasks:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span><span class="w"> </span><span class="nn">asyncio</span>
<span class="kn">import</span><span class="w"> </span><span class="nn">random</span>
<span class="kn">import</span><span class="w"> </span><span class="nn">time</span>
<span class="k">async</span> <span class="k">def</span><span class="w"> </span><span class="nf">worker</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="n">queue</span><span class="p">):</span>
 <span class="k">while</span> <span class="kc">True</span><span class="p">:</span>
 <span class="c1"># Get a &quot;work item&quot; out of the queue.</span>
 <span class="n">sleep_for</span> <span class="o">=</span> <span class="k">await</span> <span class="n">queue</span><span class="o">.</span><span class="n">get</span><span class="p">()</span>
<span class="c1"># Sleep for the &quot;sleep_for&quot; 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">sleep_for</span><span class="p">)</span>
<span class="c1"># Notify the queue that the &quot;work item&quot; has been processed.</span>
 <span class="n">queue</span><span class="o">.</span><span class="n">task_done</span><span class="p">()</span>
<span class="nb">print</span><span class="p">(</span><span class="sa">f</span><span class="s1">&#39;</span><span class="si">{</span><span class="n">name</span><span class="si">}</span><span class="s1"> has slept for </span><span class="si">{</span><span class="n">sleep_for</span><span class="si">:</span><span class="s1">.2f</span><span class="si">}</span><span class="s1"> seconds&#39;</span><span class="p">)</span>
<span class="k">async</span> <span class="k">def</span><span class="w"> </span><span class="nf">main</span><span class="p">():</span>
 <span class="c1"># Create a queue that we will use to store our &quot;workload&quot;.</span>
 <span class="n">queue</span> <span class="o">=</span> <span class="n">asyncio</span><span class="o">.</span><span class="n">Queue</span><span class="p">()</span>
<span class="c1"># Generate random timings and put them into the queue.</span>
 <span class="n">total_sleep_time</span> <span class="o">=</span> <span class="mi">0</span>
 <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="mi">20</span><span class="p">):</span>
 <span class="n">sleep_for</span> <span class="o">=</span> <span class="n">random</span><span class="o">.</span><span class="n">uniform</span><span class="p">(</span><span class="mf">0.05</span><span class="p">,</span> <span class="mf">1.0</span><span class="p">)</span>
 <span class="n">total_sleep_time</span> <span class="o">+=</span> <span class="n">sleep_for</span>
 <span class="n">queue</span><span class="o">.</span><span class="n">put_nowait</span><span class="p">(</span><span class="n">sleep_for</span><span class="p">)</span>
<span class="c1"># Create three worker tasks to process the queue concurrently.</span>
 <span class="n">tasks</span> <span class="o">=</span> <span class="p">[]</span>
 <span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="mi">3</span><span class="p">):</span>
 <span class="n">task</span> <span class="o">=</span> <span class="n">asyncio</span><span class="o">.</span><span class="n">create_task</span><span class="p">(</span><span class="n">worker</span><span class="p">(</span><span class="sa">f</span><span class="s1">&#39;worker-</span><span class="si">{</span><span class="n">i</span><span class="si">}</span><span class="s1">&#39;</span><span class="p">,</span> <span class="n">queue</span><span class="p">))</span>
 <span class="n">tasks</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">task</span><span class="p">)</span>
<span class="c1"># Wait until the queue is fully processed.</span>
 <span class="n">started_at</span> <span class="o">=</span> <span class="n">time</span><span class="o">.</span><span class="n">monotonic</span><span class="p">()</span>
 <span class="k">await</span> <span class="n">queue</span><span class="o">.</span><span class="n">join</span><span class="p">()</span>
 <span class="n">total_slept_for</span> <span class="o">=</span> <span class="n">time</span><span class="o">.</span><span class="n">monotonic</span><span class="p">()</span> <span class="o">-</span> <span class="n">started_at</span>
<span class="c1"># Cancel our worker tasks.</span>
 <span class="k">for</span> <span class="n">task</span> <span class="ow">in</span> <span class="n">tasks</span><span class="p">:</span>
 <span class="n">task</span><span class="o">.</span><span class="n">cancel</span><span class="p">()</span>
 <span class="c1"># Wait until all worker tasks are cancelled.</span>
 <span class="k">await</span> <span class="n">asyncio</span><span class="o">.</span><span class="n">gather</span><span class="p">(</span><span class="o">*</span><span class="n">tasks</span><span class="p">,</span> <span class="n">return_exceptions</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="nb">print</span><span class="p">(</span><span class="s1">&#39;====&#39;</span><span class="p">)</span>
 <span class="nb">print</span><span class="p">(</span><span class="sa">f</span><span class="s1">&#39;3 workers slept in parallel for </span><span class="si">{</span><span class="n">total_slept_for</span><span class="si">:</span><span class="s1">.2f</span><span class="si">}</span><span class="s1"> seconds&#39;</span><span class="p">)</span>
 <span class="nb">print</span><span class="p">(</span><span class="sa">f</span><span class="s1">&#39;total expected sleep time: </span><span class="si">{</span><span class="n">total_sleep_time</span><span class="si">:</span><span class="s1">.2f</span><span class="si">}</span><span class="s1"> seconds&#39;</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>
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<li><a class="reference internal" href="#">Queues</a><ul>
<li><a class="reference internal" href="#queue">Queue</a></li>
<li><a class="reference internal" href="#priority-queue">Priority Queue</a></li>
<li><a class="reference internal" href="#lifo-queue">LIFO Queue</a></li>
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