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<h3>Reference Counting</h3>
<p>Unlike programs written in Python, C extensions have to manipulate the reference count of Python objects. This is done using the following macros:</p>
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<p><b>Macro</b></P>
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<p><b>Description</b></p>
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<p><tt CLASs="monofont">Py_INCREF(</tt><i><TT CLass="monofont">obj</tT></I>
<TT class="monofont">)</tt></p>
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<p>Increments the reference count of <i><Tt clASS="monofont">obj</Tt></i>
, which must be non-<tt CLASs="monofont">NULL</tt></p>
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<p><tt claSs="monofont">Py_DECREF(</tT><i><tt Class="monofont">obj</Tt></i>
<tT CLAss="monofont">)</tt></P>
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<tD VALign="top">
<fONT Size="2">
<p>Decrements the reference count of <i><tt class="monofont">obj</tt></i>
, which must be non-<tt claSs="monofont">NULL</tT></p>
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</tR>
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<fONT Size="2">
<p><TT CLass="monofont">Py_XINCREF(</tT><I><TT class="monofont">obj</tt></i>
<tt class="monofont">)</tt></p>
</foNt></tD>
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<p>Increments the reference count of <i><tt CLASs="monofont">obj</tt></i>
, which may be <TT CLass="monofont">NULL</tT></P>
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<p><tt Class="monofont">Py_XDECREF(</Tt><i><tT CLAss="monofont">obj</tt></I>
<TT Class="monofont">)</TT></P>
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<TD Valign="top">
<font size="2">
<p>Decrements the reference count of <i><tt claSs="monofont">obj</tT></i>
, which may be <tt Class="monofont">NULL</Tt></p>
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<p>Manipulating the reference count of Python objects in C is a delicate topic, and readers are strongly advised to consult the 揈xtending and Embedding the Python Interpreter⌨️ 快捷键说明
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