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<section id="descriptor-objects">
<span id="id1"></span><h1>Descriptor Objects<a class="headerlink" href="#descriptor-objects" title="Link to this heading"></a></h1>
<p>“Descriptors” are objects that describe some attribute of an object. They are
found in the dictionary of type objects.</p>
<dl class="c var">
<dt class="sig sig-object c" id="c.PyProperty_Type">
<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyProperty_Type</span></span></span><a class="headerlink" href="#c.PyProperty_Type" title="Link to this definition"></a><br /></dt>
<dd><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>The type object for the built-in descriptor types.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyDescr_NewGetSet">
<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="sig-name descname"><span class="n"><span class="pre">PyDescr_NewGetSet</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <span class="k"><span class="pre">struct</span></span><span class="w"> </span><a class="reference internal" href="structures.html#c.PyGetSetDef" title="PyGetSetDef"><span class="n"><span class="pre">PyGetSetDef</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">getset</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDescr_NewGetSet" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyDescr_NewMember">
<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="sig-name descname"><span class="n"><span class="pre">PyDescr_NewMember</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <span class="k"><span class="pre">struct</span></span><span class="w"> </span><a class="reference internal" href="structures.html#c.PyMemberDef" title="PyMemberDef"><span class="n"><span class="pre">PyMemberDef</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">meth</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDescr_NewMember" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyDescr_NewMethod">
<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="sig-name descname"><span class="n"><span class="pre">PyDescr_NewMethod</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <span class="k"><span class="pre">struct</span></span><span class="w"> </span><a class="reference internal" href="structures.html#c.PyMethodDef" title="PyMethodDef"><span class="n"><span class="pre">PyMethodDef</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">meth</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDescr_NewMethod" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyDescr_NewWrapper">
<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="sig-name descname"><span class="n"><span class="pre">PyDescr_NewWrapper</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <span class="k"><span class="pre">struct</span></span><span class="w"> </span><span class="n"><span class="pre">wrapperbase</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">wrapper</span></span>, <span class="kt"><span class="pre">void</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">wrapped</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDescr_NewWrapper" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyDescr_NewClassMethod">
<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="sig-name descname"><span class="n"><span class="pre">PyDescr_NewClassMethod</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">type</span></span>, <a class="reference internal" href="structures.html#c.PyMethodDef" title="PyMethodDef"><span class="n"><span class="pre">PyMethodDef</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">method</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDescr_NewClassMethod" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em></dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyDescr_IsData">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyDescr_IsData</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">descr</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyDescr_IsData" title="Link to this definition"></a><br /></dt>
<dd><p>Return non-zero if the descriptor objects <em>descr</em> describes a data attribute, or
<code class="docutils literal notranslate"><span class="pre">0</span></code> if it describes a method. <em>descr</em> must be a descriptor object; there is
no error checking.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyWrapper_New">
<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="sig-name descname"><span class="n"><span class="pre">PyWrapper_New</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="p"><span class="pre">*</span></span>, <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="p"><span class="pre">*</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyWrapper_New" title="Link to this definition"></a><br /></dt>
<dd><em class="refcount return_new_ref">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em></dd></dl>
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