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<li><a class="reference internal" href="#">Object Life Cycle</a><ul>
<li><a class="reference internal" href="#life-events">Life Events</a></li>
<li><a class="reference internal" href="#cyclic-isolate-destruction">Cyclic Isolate Destruction</a></li>
<li><a class="reference internal" href="#functions">Functions</a></li>
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<section id="object-life-cycle">
<span id="life-cycle"></span><h1>Object Life Cycle<a class="headerlink" href="#object-life-cycle" title="Link to this heading">¶</a></h1>
<p>This section explains how a type’s slots relate to each other throughout the
life of an object. It is not intended to be a complete canonical reference for
the slots; instead, refer to the slot-specific documentation in
<a class="reference internal" href="typeobj.html#type-structs"><span class="std std-ref">Type Object Structures</span></a> for details about a particular slot.</p>
<section id="life-events">
<h2>Life Events<a class="headerlink" href="#life-events" title="Link to this heading">¶</a></h2>
<p>The figure below illustrates the order of events that can occur throughout an
object’s life. An arrow from <em>A</em> to <em>B</em> indicates that event <em>B</em> can occur
after event <em>A</em> has occurred, with the arrow’s label indicating the condition
that must be true for <em>B</em> to occur after <em>A</em>.</p>
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<text text-anchor="start" x="54.05" y="-624.1" font-family="serif,serif" font-style="italic" font-size="12.00">  not in a  </text>
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<g id="a_life_events_graph_node7"><a xlink:title="marked as finalized?">
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<text text-anchor="start" x="332.42" y="-379.35" font-family="serif,serif" font-style="italic" font-size="12.00">  isolate  </text>
<text text-anchor="start" x="331.3" y="-365.1" font-family="serif,serif" font-style="italic" font-size="12.00">  (no GC  </text>
<text text-anchor="start" x="326.8" y="-350.85" font-family="serif,serif" font-style="italic" font-size="12.00">  support)  </text>
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<text text-anchor="start" x="269.2" y="-316.73" font-family="serif,serif" font-style="italic" font-size="12.00">  yes  </text>
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<title>tp_finalize->tp_clear</title>
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<text text-anchor="start" x="164.3" y="-282.6" font-family="serif,serif" font-style="italic" font-size="12.00">  no refs or   </text>
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<text text-anchor="start" x="7.8" y="-200.1" font-family="serif,serif" font-style="italic" font-size="12.00">  recommended</text>
<text text-anchor="start" x="25.8" y="-185.85" font-family="serif,serif" font-style="italic" font-size="12.00">  call (see</text>
<text text-anchor="start" x="13.05" y="-171.6" font-family="serif,serif" font-style="italic" font-size="12.00">  explanation)</text>
</a>
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<title>tp_finalize->tp_dealloc</title>
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<text text-anchor="start" x="146.05" y="-185.85" font-family="serif,serif" font-style="italic" font-size="12.00">   no refs  </text>
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<text text-anchor="start" x="260.67" y="-192.97" font-family="serif,serif" font-style="italic" font-size="12.00">  cyclic  </text>
<text text-anchor="start" x="258.05" y="-178.72" font-family="serif,serif" font-style="italic" font-size="12.00">  isolate  </text>
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<text text-anchor="start" x="209.8" y="-137.22" font-family="serif,serif" font-style="italic" font-size="12.00">  no refs  </text>
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<text text-anchor="start" x="200.8" y="-47.85" font-family="serif,serif" font-style="italic" font-size="12.00">    direct call  </text>
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<p>Explanation:</p>
<ul class="simple">
<li><p>When a new object is constructed by calling its type:</p>
<ol class="arabic simple">
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_new" title="PyTypeObject.tp_new"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_new</span></code></a> is called to create a new object.</p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_alloc" title="PyTypeObject.tp_alloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_alloc</span></code></a> is directly called by
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_new" title="PyTypeObject.tp_new"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_new</span></code></a> to allocate the memory for the new
object.</p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_init" title="PyTypeObject.tp_init"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code></a> initializes the newly created object.
<code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code> can be called again to re-initialize an object, if
desired. The <code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code> call can also be skipped entirely,
for example by Python code calling <a class="reference internal" href="../reference/datamodel.html#object.__new__" title="object.__new__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__new__()</span></code></a>.</p></li>
</ol>
</li>
<li><p>After <code class="xref c c-member docutils literal notranslate"><span class="pre">tp_init</span></code> completes, the object is ready to use.</p></li>
<li><p>Some time after the last reference to an object is removed:</p>
<ol class="arabic simple">
<li><p>If an object is not marked as <em>finalized</em>, it might be finalized by
marking it as <em>finalized</em> and calling its
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> function. Python does
<em>not</em> finalize an object when the last reference to it is deleted; use
<a class="reference internal" href="#c.PyObject_CallFinalizerFromDealloc" title="PyObject_CallFinalizerFromDealloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CallFinalizerFromDealloc()</span></code></a> to ensure that
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> is always called.</p></li>
<li><p>If the object is marked as finalized,
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> might be called by the garbage collector
to clear references held by the object. It is <em>not</em> called when the
object’s reference count reaches zero.</p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> is called to destroy the object.
To avoid code duplication, <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> typically
calls into <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> to free up the object’s
references.</p></li>
<li><p>When <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> finishes object destruction,
it directly calls <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_free" title="PyTypeObject.tp_free"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_free</span></code></a> (usually set to
<a class="reference internal" href="memory.html#c.PyObject_Free" title="PyObject_Free"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_Free()</span></code></a> or <a class="reference internal" href="gcsupport.html#c.PyObject_GC_Del" title="PyObject_GC_Del"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_GC_Del()</span></code></a> automatically as
appropriate for the type) to deallocate the memory.</p></li>
</ol>
</li>
<li><p>The <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> function is permitted to add a
reference to the object if desired. If it does, the object is
<em>resurrected</em>, preventing its pending destruction. (Only
<code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code> is allowed to resurrect an object;
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> and
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> cannot without calling into
<code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code>.) Resurrecting an object may
or may not cause the object’s <em>finalized</em> mark to be removed. Currently,
Python does not remove the <em>finalized</em> mark from a resurrected object if
it supports garbage collection (i.e., the <a class="reference internal" href="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 is set) but does remove the mark if the object does not support
garbage collection; either or both of these behaviors may change in the
future.</p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> can optionally call
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> via
<a class="reference internal" href="#c.PyObject_CallFinalizerFromDealloc" title="PyObject_CallFinalizerFromDealloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CallFinalizerFromDealloc()</span></code></a> if it wishes to reuse that
code to help with object destruction. This is recommended because it
guarantees that <code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code> is always called before
destruction. See the <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> documentation
for example code.</p></li>
<li><p>If the object is a member of a <a class="reference internal" href="../glossary.html#term-cyclic-isolate"><span class="xref std std-term">cyclic isolate</span></a> and either
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> fails to break the reference cycle or
the cyclic isolate is not detected (perhaps <a class="reference internal" href="../library/gc.html#gc.disable" title="gc.disable"><code class="xref py py-func docutils literal notranslate"><span class="pre">gc.disable()</span></code></a> was called,
or the <a class="reference internal" href="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 was erroneously omitted in one
of the involved types), the objects remain indefinitely uncollectable
(they “leak”). See <a class="reference internal" href="../library/gc.html#gc.garbage" title="gc.garbage"><code class="xref py py-data docutils literal notranslate"><span class="pre">gc.garbage</span></code></a>.</p></li>
</ul>
<p>If the object is marked as supporting garbage collection (the
<a class="reference internal" href="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 is set in
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_flags" title="PyTypeObject.tp_flags"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_flags</span></code></a>), the following events are also possible:</p>
<ul class="simple">
<li><p>The garbage collector occasionally calls
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_traverse" title="PyTypeObject.tp_traverse"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_traverse</span></code></a> to identify <a class="reference internal" href="../glossary.html#term-cyclic-isolate"><span class="xref std std-term">cyclic isolates</span></a>.</p></li>
<li><p>When the garbage collector discovers a <a class="reference internal" href="../glossary.html#term-cyclic-isolate"><span class="xref std std-term">cyclic isolate</span></a>, it
finalizes one of the objects in the group by marking it as <em>finalized</em> and
calling its <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> function, if it has one.
This repeats until the cyclic isolate doesn’t exist or all of the objects
have been finalized.</p></li>
<li><p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> is permitted to resurrect the object
by adding a reference from outside the <a class="reference internal" href="../glossary.html#term-cyclic-isolate"><span class="xref std std-term">cyclic isolate</span></a>. The new
reference causes the group of objects to no longer form a cyclic isolate
(the reference cycle may still exist, but if it does the objects are no
longer isolated).</p></li>
<li><p>When the garbage collector discovers a <a class="reference internal" href="../glossary.html#term-cyclic-isolate"><span class="xref std std-term">cyclic isolate</span></a> and all of
the objects in the group have already been marked as <em>finalized</em>, the
garbage collector clears one or more of the uncleared objects in the group
(possibly concurrently) by calling each’s
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> function. This repeats as long as the
cyclic isolate still exists and not all of the objects have been cleared.</p></li>
</ul>
</div>
</section>
<section id="cyclic-isolate-destruction">
<h2>Cyclic Isolate Destruction<a class="headerlink" href="#cyclic-isolate-destruction" title="Link to this heading">¶</a></h2>
<p>Listed below are the stages of life of a hypothetical <a class="reference internal" href="../glossary.html#term-cyclic-isolate"><span class="xref std std-term">cyclic isolate</span></a>
that continues to exist after each member object is finalized or cleared. It
is a memory leak if a cyclic isolate progresses through all of these stages; it should
vanish once all objects are cleared, if not sooner. A cyclic isolate can
vanish either because the reference cycle is broken or because the objects are
no longer isolated due to finalizer resurrection (see
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a>).</p>
<ol class="arabic simple" start="0">
<li><p><strong>Reachable</strong> (not yet a cyclic isolate): All objects are in their normal,
reachable state. A reference cycle could exist, but an external reference
means the objects are not yet isolated.</p></li>
<li><p><strong>Unreachable but consistent:</strong> The final reference from outside the cyclic
group of objects has been removed, causing the objects to become isolated
(thus a cyclic isolate is born). None of the group’s objects have been
finalized or cleared yet. The cyclic isolate remains at this stage until
some future run of the garbage collector (not necessarily the next run
because the next run might not scan every object).</p></li>
<li><p><strong>Mix of finalized and not finalized:</strong> Objects in a cyclic isolate are
finalized one at a time, which means that there is a period of time when the
cyclic isolate is composed of a mix of finalized and non-finalized objects.
Finalization order is unspecified, so it can appear random. A finalized
object must behave in a sane manner when non-finalized objects interact with
it, and a non-finalized object must be able to tolerate the finalization of
an arbitrary subset of its referents.</p></li>
<li><p><strong>All finalized:</strong> All objects in a cyclic isolate are finalized before any
of them are cleared.</p></li>
<li><p><strong>Mix of finalized and cleared:</strong> The objects can be cleared serially or
concurrently (but with the <a class="reference internal" href="../glossary.html#term-GIL"><span class="xref std std-term">GIL</span></a> held); either way, some will finish
before others. A finalized object must be able to tolerate the clearing of
a subset of its referents. <span class="target" id="index-0"></span><a class="pep reference external" href="https://peps.python.org/pep-0442/"><strong>PEP 442</strong></a> calls this stage “cyclic trash”.</p></li>
<li><p><strong>Leaked:</strong> If a cyclic isolate still exists after all objects in the group
have been finalized and cleared, then the objects remain indefinitely
uncollectable (see <a class="reference internal" href="../library/gc.html#gc.garbage" title="gc.garbage"><code class="xref py py-data docutils literal notranslate"><span class="pre">gc.garbage</span></code></a>). It is a bug if a cyclic isolate
reaches this stage—it means the <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> methods
of the participating objects have failed to break the reference cycle as
required.</p></li>
</ol>
<p>If <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> did not exist, then Python would have no
way to safely break a reference cycle. Simply destroying an object in a cyclic
isolate would result in a dangling pointer, triggering undefined behavior when
an object referencing the destroyed object is itself destroyed. The clearing
step makes object destruction a two-phase process: first
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> is called to partially destroy the objects
enough to detangle them from each other, then
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> is called to complete the destruction.</p>
<p>Unlike clearing, finalization is not a phase of destruction. A finalized
object must still behave properly by continuing to fulfill its design
contracts. An object’s finalizer is allowed to execute arbitrary Python code,
and is even allowed to prevent the impending destruction by adding a reference.
The finalizer is only related to destruction by call order—if it runs, it runs
before destruction, which starts with <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> (if
called) and concludes with <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a>.</p>
<p>The finalization step is not necessary to safely reclaim the objects in a
cyclic isolate, but its existence makes it easier to design types that behave
in a sane manner when objects are cleared. Clearing an object might
necessarily leave it in a broken, partially destroyed state—it might be
unsafe to call any of the cleared object’s methods or access any of its
attributes. With finalization, only finalized objects can possibly interact
with cleared objects; non-finalized objects are guaranteed to interact with
only non-cleared (but potentially finalized) objects.</p>
<p>To summarize the possible interactions:</p>
<ul class="simple">
<li><p>A non-finalized object might have references to or from non-finalized and
finalized objects, but not to or from cleared objects.</p></li>
<li><p>A finalized object might have references to or from non-finalized, finalized,
and cleared objects.</p></li>
<li><p>A cleared object might have references to or from finalized and cleared
objects, but not to or from non-finalized objects.</p></li>
</ul>
<p>Without any reference cycles, an object can be simply destroyed once its last
reference is deleted; the finalization and clearing steps are not necessary to
safely reclaim unused objects. However, it can be useful to automatically call
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> and <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a>
before destruction anyway because type design is simplified when all objects
always experience the same series of events regardless of whether they
participated in a cyclic isolate. Python currently only calls
<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> and <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_clear" title="PyTypeObject.tp_clear"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_clear</span></code></a> as
needed to destroy a cyclic isolate; this may change in a future version.</p>
</section>
<section id="functions">
<h2>Functions<a class="headerlink" href="#functions" title="Link to this heading">¶</a></h2>
<p>To allocate and free memory, see <a class="reference internal" href="allocation.html#allocating-objects"><span class="std std-ref">Allocating Objects on the Heap</span></a>.</p>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyObject_CallFinalizer">
<span class="kt"><span class="pre">void</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyObject_CallFinalizer</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">op</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallFinalizer" title="Link to this definition">¶</a><br /></dt>
<dd><p>Finalizes the object as described in <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a>.
Call this function (or <a class="reference internal" href="#c.PyObject_CallFinalizerFromDealloc" title="PyObject_CallFinalizerFromDealloc"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CallFinalizerFromDealloc()</span></code></a>) instead
of calling <a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_finalize" title="PyTypeObject.tp_finalize"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code></a> directly because this
function may deduplicate multiple calls to <code class="xref c c-member docutils literal notranslate"><span class="pre">tp_finalize</span></code>.
Currently, calls are only deduplicated if the type supports garbage
collection (i.e., the <a class="reference internal" href="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 is set); this may
change in the future.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyObject_CallFinalizerFromDealloc">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyObject_CallFinalizerFromDealloc</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">op</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyObject_CallFinalizerFromDealloc" title="Link to this definition">¶</a><br /></dt>
<dd><p>Same as <a class="reference internal" href="#c.PyObject_CallFinalizer" title="PyObject_CallFinalizer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyObject_CallFinalizer()</span></code></a> but meant to be called at the
beginning of the object’s destructor (<a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a>).
There must not be any references to the object. If the object’s finalizer
resurrects the object, this function returns -1; no further destruction
should happen. Otherwise, this function returns 0 and destruction can
continue normally.</p>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="typeobj.html#c.PyTypeObject.tp_dealloc" title="PyTypeObject.tp_dealloc"><code class="xref c c-member docutils literal notranslate"><span class="pre">tp_dealloc</span></code></a> for example code.</p>
</div>
</dd></dl>
</section>
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<li><a class="reference internal" href="#">Object Life Cycle</a><ul>
<li><a class="reference internal" href="#life-events">Life Events</a></li>
<li><a class="reference internal" href="#cyclic-isolate-destruction">Cyclic Isolate Destruction</a></li>
<li><a class="reference internal" href="#functions">Functions</a></li>
</ul>
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