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<div class="section" id="object-protocol">
<span id="object"></span><h1>Object Protocol<a class="headerlink" href="#object-protocol" title="Permalink to this headline">¶</a></h1>
<dl class="function">
<dt id="PyObject_Print">
int <tt class="descname">PyObject_Print</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, FILE<em> *fp</em>, int<em> flags</em><big>)</big><a class="headerlink" href="#PyObject_Print" title="Permalink to this definition">¶</a></dt>
<dd><p>Print an object <em>o</em>, on file <em>fp</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on error. The flags argument
is used to enable certain printing options. The only option currently supported
is <tt class="xref py py-const docutils literal"><span class="pre">Py_PRINT_RAW</span></tt>; if given, the <a class="reference internal" href="../library/functions.html#str" title="str"><tt class="xref py py-func docutils literal"><span class="pre">str()</span></tt></a> of the object is written
instead of the <a class="reference internal" href="../library/functions.html#repr" title="repr"><tt class="xref py py-func docutils literal"><span class="pre">repr()</span></tt></a>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_HasAttr">
int <tt class="descname">PyObject_HasAttr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *attr_name</em><big>)</big><a class="headerlink" href="#PyObject_HasAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <tt class="docutils literal"><span class="pre">1</span></tt> if <em>o</em> has the attribute <em>attr_name</em>, and <tt class="docutils literal"><span class="pre">0</span></tt> otherwise. This
is equivalent to the Python expression <tt class="docutils literal"><span class="pre">hasattr(o,</span> <span class="pre">attr_name)</span></tt>. This function
always succeeds.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_HasAttrString">
int <tt class="descname">PyObject_HasAttrString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em><big>)</big><a class="headerlink" href="#PyObject_HasAttrString" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <tt class="docutils literal"><span class="pre">1</span></tt> if <em>o</em> has the attribute <em>attr_name</em>, and <tt class="docutils literal"><span class="pre">0</span></tt> otherwise. This
is equivalent to the Python expression <tt class="docutils literal"><span class="pre">hasattr(o,</span> <span class="pre">attr_name)</span></tt>. This function
always succeeds.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_GetAttr">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_GetAttr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *attr_name</em><big>)</big><a class="headerlink" href="#PyObject_GetAttr" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Retrieve an attribute named <em>attr_name</em> from object <em>o</em>. Returns the attribute
value on success, or <em>NULL</em> on failure. This is the equivalent of the Python
expression <tt class="docutils literal"><span class="pre">o.attr_name</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_GetAttrString">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_GetAttrString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em><big>)</big><a class="headerlink" href="#PyObject_GetAttrString" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Retrieve an attribute named <em>attr_name</em> from object <em>o</em>. Returns the attribute
value on success, or <em>NULL</em> on failure. This is the equivalent of the Python
expression <tt class="docutils literal"><span class="pre">o.attr_name</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_GenericGetAttr">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_GenericGetAttr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *name</em><big>)</big><a class="headerlink" href="#PyObject_GenericGetAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Generic attribute getter function that is meant to be put into a type
object’s <tt class="docutils literal"><span class="pre">tp_getattro</span></tt> slot. It looks for a descriptor in the dictionary
of classes in the object’s MRO as well as an attribute in the object’s
<tt class="xref py py-attr docutils literal"><span class="pre">__dict__</span></tt> (if present). As outlined in <a class="reference internal" href="../reference/datamodel.html#descriptors"><em>Implementing Descriptors</em></a>, data
descriptors take preference over instance attributes, while non-data
descriptors don’t. Otherwise, an <a class="reference internal" href="../library/exceptions.html#AttributeError" title="AttributeError"><tt class="xref py py-exc docutils literal"><span class="pre">AttributeError</span></tt></a> is raised.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_SetAttr">
int <tt class="descname">PyObject_SetAttr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *attr_name</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *v</em><big>)</big><a class="headerlink" href="#PyObject_SetAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Set the value of the attribute named <em>attr_name</em>, for object <em>o</em>, to the value
<em>v</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on failure. This is the equivalent of the Python statement
<tt class="docutils literal"><span class="pre">o.attr_name</span> <span class="pre">=</span> <span class="pre">v</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_SetAttrString">
int <tt class="descname">PyObject_SetAttrString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *v</em><big>)</big><a class="headerlink" href="#PyObject_SetAttrString" title="Permalink to this definition">¶</a></dt>
<dd><p>Set the value of the attribute named <em>attr_name</em>, for object <em>o</em>, to the value
<em>v</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on failure. This is the equivalent of the Python statement
<tt class="docutils literal"><span class="pre">o.attr_name</span> <span class="pre">=</span> <span class="pre">v</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_GenericSetAttr">
int <tt class="descname">PyObject_GenericSetAttr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *name</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *value</em><big>)</big><a class="headerlink" href="#PyObject_GenericSetAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Generic attribute setter function that is meant to be put into a type
object’s <tt class="docutils literal"><span class="pre">tp_setattro</span></tt> slot. It looks for a data descriptor in the
dictionary of classes in the object’s MRO, and if found it takes preference
over setting the attribute in the instance dictionary. Otherwise, the
attribute is set in the object’s <tt class="xref py py-attr docutils literal"><span class="pre">__dict__</span></tt> (if present). Otherwise,
an <a class="reference internal" href="../library/exceptions.html#AttributeError" title="AttributeError"><tt class="xref py py-exc docutils literal"><span class="pre">AttributeError</span></tt></a> is raised and <tt class="docutils literal"><span class="pre">-1</span></tt> is returned.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_DelAttr">
int <tt class="descname">PyObject_DelAttr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *attr_name</em><big>)</big><a class="headerlink" href="#PyObject_DelAttr" title="Permalink to this definition">¶</a></dt>
<dd><p>Delete attribute named <em>attr_name</em>, for object <em>o</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on failure.
This is the equivalent of the Python statement <tt class="docutils literal"><span class="pre">del</span> <span class="pre">o.attr_name</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_DelAttrString">
int <tt class="descname">PyObject_DelAttrString</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, const char<em> *attr_name</em><big>)</big><a class="headerlink" href="#PyObject_DelAttrString" title="Permalink to this definition">¶</a></dt>
<dd><p>Delete attribute named <em>attr_name</em>, for object <em>o</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on failure.
This is the equivalent of the Python statement <tt class="docutils literal"><span class="pre">del</span> <span class="pre">o.attr_name</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_RichCompare">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_RichCompare</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o1</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o2</em>, int<em> opid</em><big>)</big><a class="headerlink" href="#PyObject_RichCompare" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Compare the values of <em>o1</em> and <em>o2</em> using the operation specified by <em>opid</em>,
which must be one of <tt class="xref py py-const docutils literal"><span class="pre">Py_LT</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">Py_LE</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">Py_EQ</span></tt>,
<tt class="xref py py-const docutils literal"><span class="pre">Py_NE</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">Py_GT</span></tt>, or <tt class="xref py py-const docutils literal"><span class="pre">Py_GE</span></tt>, corresponding to <tt class="docutils literal"><span class="pre"><</span></tt>,
<tt class="docutils literal"><span class="pre"><=</span></tt>, <tt class="docutils literal"><span class="pre">==</span></tt>, <tt class="docutils literal"><span class="pre">!=</span></tt>, <tt class="docutils literal"><span class="pre">></span></tt>, or <tt class="docutils literal"><span class="pre">>=</span></tt> respectively. This is the equivalent of
the Python expression <tt class="docutils literal"><span class="pre">o1</span> <span class="pre">op</span> <span class="pre">o2</span></tt>, where <tt class="docutils literal"><span class="pre">op</span></tt> is the operator corresponding
to <em>opid</em>. Returns the value of the comparison on success, or <em>NULL</em> on failure.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_RichCompareBool">
int <tt class="descname">PyObject_RichCompareBool</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o1</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o2</em>, int<em> opid</em><big>)</big><a class="headerlink" href="#PyObject_RichCompareBool" title="Permalink to this definition">¶</a></dt>
<dd><p>Compare the values of <em>o1</em> and <em>o2</em> using the operation specified by <em>opid</em>,
which must be one of <tt class="xref py py-const docutils literal"><span class="pre">Py_LT</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">Py_LE</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">Py_EQ</span></tt>,
<tt class="xref py py-const docutils literal"><span class="pre">Py_NE</span></tt>, <tt class="xref py py-const docutils literal"><span class="pre">Py_GT</span></tt>, or <tt class="xref py py-const docutils literal"><span class="pre">Py_GE</span></tt>, corresponding to <tt class="docutils literal"><span class="pre"><</span></tt>,
<tt class="docutils literal"><span class="pre"><=</span></tt>, <tt class="docutils literal"><span class="pre">==</span></tt>, <tt class="docutils literal"><span class="pre">!=</span></tt>, <tt class="docutils literal"><span class="pre">></span></tt>, or <tt class="docutils literal"><span class="pre">>=</span></tt> respectively. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on error,
<tt class="docutils literal"><span class="pre">0</span></tt> if the result is false, <tt class="docutils literal"><span class="pre">1</span></tt> otherwise. This is the equivalent of the
Python expression <tt class="docutils literal"><span class="pre">o1</span> <span class="pre">op</span> <span class="pre">o2</span></tt>, where <tt class="docutils literal"><span class="pre">op</span></tt> is the operator corresponding to
<em>opid</em>.</p>
</dd></dl>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">If <em>o1</em> and <em>o2</em> are the same object, <a class="reference internal" href="#PyObject_RichCompareBool" title="PyObject_RichCompareBool"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_RichCompareBool()</span></tt></a>
will always return <tt class="docutils literal"><span class="pre">1</span></tt> for <tt class="xref py py-const docutils literal"><span class="pre">Py_EQ</span></tt> and <tt class="docutils literal"><span class="pre">0</span></tt> for <tt class="xref py py-const docutils literal"><span class="pre">Py_NE</span></tt>.</p>
</div>
<dl class="function">
<dt id="PyObject_Repr">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_Repr</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Repr" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-0">Compute a string representation of object <em>o</em>. Returns the string
representation on success, <em>NULL</em> on failure. This is the equivalent of the
Python expression <tt class="docutils literal"><span class="pre">repr(o)</span></tt>. Called by the <a class="reference internal" href="../library/functions.html#repr" title="repr"><tt class="xref py py-func docutils literal"><span class="pre">repr()</span></tt></a> built-in function.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_ASCII">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_ASCII</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_ASCII" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-1">As <a class="reference internal" href="#PyObject_Repr" title="PyObject_Repr"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_Repr()</span></tt></a>, compute a string representation of object <em>o</em>, but
escape the non-ASCII characters in the string returned by
<a class="reference internal" href="#PyObject_Repr" title="PyObject_Repr"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_Repr()</span></tt></a> with <tt class="docutils literal"><span class="pre">\x</span></tt>, <tt class="docutils literal"><span class="pre">\u</span></tt> or <tt class="docutils literal"><span class="pre">\U</span></tt> escapes. This generates
a string similar to that returned by <a class="reference internal" href="#PyObject_Repr" title="PyObject_Repr"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_Repr()</span></tt></a> in Python 2.
Called by the <a class="reference internal" href="../library/functions.html#ascii" title="ascii"><tt class="xref py py-func docutils literal"><span class="pre">ascii()</span></tt></a> built-in function.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Str">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_Str</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Str" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-2">Compute a string representation of object <em>o</em>. Returns the string
representation on success, <em>NULL</em> on failure. This is the equivalent of the
Python expression <tt class="docutils literal"><span class="pre">str(o)</span></tt>. Called by the <a class="reference internal" href="../library/functions.html#str" title="str"><tt class="xref py py-func docutils literal"><span class="pre">str()</span></tt></a> built-in function
and, therefore, by the <a class="reference internal" href="../library/functions.html#print" title="print"><tt class="xref py py-func docutils literal"><span class="pre">print()</span></tt></a> function.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Bytes">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_Bytes</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Bytes" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-3">Compute a bytes representation of object <em>o</em>. <em>NULL</em> is returned on
failure and a bytes object on success. This is equivalent to the Python
expression <tt class="docutils literal"><span class="pre">bytes(o)</span></tt>, when <em>o</em> is not an integer. Unlike <tt class="docutils literal"><span class="pre">bytes(o)</span></tt>,
a TypeError is raised when <em>o</em> is an integer instead of a zero-initialized
bytes object.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_IsInstance">
int <tt class="descname">PyObject_IsInstance</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *inst</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *cls</em><big>)</big><a class="headerlink" href="#PyObject_IsInstance" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <tt class="docutils literal"><span class="pre">1</span></tt> if <em>inst</em> is an instance of the class <em>cls</em> or a subclass of
<em>cls</em>, or <tt class="docutils literal"><span class="pre">0</span></tt> if not. On error, returns <tt class="docutils literal"><span class="pre">-1</span></tt> and sets an exception. If
<em>cls</em> is a type object rather than a class object, <a class="reference internal" href="#PyObject_IsInstance" title="PyObject_IsInstance"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_IsInstance()</span></tt></a>
returns <tt class="docutils literal"><span class="pre">1</span></tt> if <em>inst</em> is of type <em>cls</em>. If <em>cls</em> is a tuple, the check will
be done against every entry in <em>cls</em>. The result will be <tt class="docutils literal"><span class="pre">1</span></tt> when at least one
of the checks returns <tt class="docutils literal"><span class="pre">1</span></tt>, otherwise it will be <tt class="docutils literal"><span class="pre">0</span></tt>. If <em>inst</em> is not a
class instance and <em>cls</em> is neither a type object, nor a class object, nor a
tuple, <em>inst</em> must have a <tt class="xref py py-attr docutils literal"><span class="pre">__class__</span></tt> attribute — the class relationship
of the value of that attribute with <em>cls</em> will be used to determine the result
of this function.</p>
</dd></dl>
<p>Subclass determination is done in a fairly straightforward way, but includes a
wrinkle that implementors of extensions to the class system may want to be aware
of. If <tt class="xref py py-class docutils literal"><span class="pre">A</span></tt> and <tt class="xref py py-class docutils literal"><span class="pre">B</span></tt> are class objects, <tt class="xref py py-class docutils literal"><span class="pre">B</span></tt> is a subclass of
<tt class="xref py py-class docutils literal"><span class="pre">A</span></tt> if it inherits from <tt class="xref py py-class docutils literal"><span class="pre">A</span></tt> either directly or indirectly. If
either is not a class object, a more general mechanism is used to determine the
class relationship of the two objects. When testing if <em>B</em> is a subclass of
<em>A</em>, if <em>A</em> is <em>B</em>, <a class="reference internal" href="#PyObject_IsSubclass" title="PyObject_IsSubclass"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_IsSubclass()</span></tt></a> returns true. If <em>A</em> and <em>B</em>
are different objects, <em>B</em>‘s <tt class="xref py py-attr docutils literal"><span class="pre">__bases__</span></tt> attribute is searched in a
depth-first fashion for <em>A</em> — the presence of the <tt class="xref py py-attr docutils literal"><span class="pre">__bases__</span></tt> attribute
is considered sufficient for this determination.</p>
<dl class="function">
<dt id="PyObject_IsSubclass">
int <tt class="descname">PyObject_IsSubclass</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *derived</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *cls</em><big>)</big><a class="headerlink" href="#PyObject_IsSubclass" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <tt class="docutils literal"><span class="pre">1</span></tt> if the class <em>derived</em> is identical to or derived from the class
<em>cls</em>, otherwise returns <tt class="docutils literal"><span class="pre">0</span></tt>. In case of an error, returns <tt class="docutils literal"><span class="pre">-1</span></tt>. If <em>cls</em>
is a tuple, the check will be done against every entry in <em>cls</em>. The result will
be <tt class="docutils literal"><span class="pre">1</span></tt> when at least one of the checks returns <tt class="docutils literal"><span class="pre">1</span></tt>, otherwise it will be
<tt class="docutils literal"><span class="pre">0</span></tt>. If either <em>derived</em> or <em>cls</em> is not an actual class object (or tuple),
this function uses the generic algorithm described above.</p>
</dd></dl>
<dl class="function">
<dt id="PyCallable_Check">
int <tt class="descname">PyCallable_Check</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyCallable_Check" title="Permalink to this definition">¶</a></dt>
<dd><p>Determine if the object <em>o</em> is callable. Return <tt class="docutils literal"><span class="pre">1</span></tt> if the object is callable
and <tt class="docutils literal"><span class="pre">0</span></tt> otherwise. This function always succeeds.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Call">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_Call</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *callable_object</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *args</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *kw</em><big>)</big><a class="headerlink" href="#PyObject_Call" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable_object</em>, with arguments given by the
tuple <em>args</em>, and named arguments given by the dictionary <em>kw</em>. If no named
arguments are needed, <em>kw</em> may be <em>NULL</em>. <em>args</em> must not be <em>NULL</em>, use an
empty tuple if no arguments are needed. Returns the result of the call on
success, or <em>NULL</em> on failure. This is the equivalent of the Python expression
<tt class="docutils literal"><span class="pre">callable_object(*args,</span> <span class="pre">**kw)</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_CallObject">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_CallObject</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *callable_object</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *args</em><big>)</big><a class="headerlink" href="#PyObject_CallObject" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable_object</em>, with arguments given by the
tuple <em>args</em>. If no arguments are needed, then <em>args</em> may be <em>NULL</em>. Returns
the result of the call on success, or <em>NULL</em> on failure. This is the equivalent
of the Python expression <tt class="docutils literal"><span class="pre">callable_object(*args)</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_CallFunction">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_CallFunction</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *callable</em>, char<em> *format</em>, ...<big>)</big><a class="headerlink" href="#PyObject_CallFunction" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable</em>, with a variable number of C arguments.
The C arguments are described using a <a class="reference internal" href="arg.html#Py_BuildValue" title="Py_BuildValue"><tt class="xref c c-func docutils literal"><span class="pre">Py_BuildValue()</span></tt></a> style format
string. The format may be <em>NULL</em>, indicating that no arguments are provided.
Returns the result of the call on success, or <em>NULL</em> on failure. This is the
equivalent of the Python expression <tt class="docutils literal"><span class="pre">callable(*args)</span></tt>. Note that if you only
pass <a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject</span> <span class="pre">*</span></tt></a> args, <a class="reference internal" href="#PyObject_CallFunctionObjArgs" title="PyObject_CallFunctionObjArgs"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_CallFunctionObjArgs()</span></tt></a> is a
faster alternative.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_CallMethod">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_CallMethod</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, char<em> *method</em>, char<em> *format</em>, ...<big>)</big><a class="headerlink" href="#PyObject_CallMethod" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call the method named <em>method</em> of object <em>o</em> with a variable number of C
arguments. The C arguments are described by a <a class="reference internal" href="arg.html#Py_BuildValue" title="Py_BuildValue"><tt class="xref c c-func docutils literal"><span class="pre">Py_BuildValue()</span></tt></a> format
string that should produce a tuple. The format may be <em>NULL</em>, indicating that
no arguments are provided. Returns the result of the call on success, or <em>NULL</em>
on failure. This is the equivalent of the Python expression <tt class="docutils literal"><span class="pre">o.method(args)</span></tt>.
Note that if you only pass <a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject</span> <span class="pre">*</span></tt></a> args,
<a class="reference internal" href="#PyObject_CallMethodObjArgs" title="PyObject_CallMethodObjArgs"><tt class="xref c c-func docutils literal"><span class="pre">PyObject_CallMethodObjArgs()</span></tt></a> is a faster alternative.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_CallFunctionObjArgs">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_CallFunctionObjArgs</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *callable</em>, ..., NULL<big>)</big><a class="headerlink" href="#PyObject_CallFunctionObjArgs" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Call a callable Python object <em>callable</em>, with a variable number of
<a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject*</span></tt></a> arguments. The arguments are provided as a variable number
of parameters followed by <em>NULL</em>. Returns the result of the call on success, or
<em>NULL</em> on failure.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_CallMethodObjArgs">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_CallMethodObjArgs</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *name</em>, ..., NULL<big>)</big><a class="headerlink" href="#PyObject_CallMethodObjArgs" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Calls a method of the object <em>o</em>, where the name of the method is given as a
Python string object in <em>name</em>. It is called with a variable number of
<a class="reference internal" href="structures.html#PyObject" title="PyObject"><tt class="xref c c-type docutils literal"><span class="pre">PyObject*</span></tt></a> arguments. The arguments are provided as a variable number
of parameters followed by <em>NULL</em>. Returns the result of the call on success, or
<em>NULL</em> on failure.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Hash">
Py_hash_t <tt class="descname">PyObject_Hash</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Hash" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-4">Compute and return the hash value of an object <em>o</em>. On failure, return <tt class="docutils literal"><span class="pre">-1</span></tt>.
This is the equivalent of the Python expression <tt class="docutils literal"><span class="pre">hash(o)</span></tt>.</p>
<p class="versionchanged">
<span class="versionmodified">Changed in version 3.2: </span>The return type is now Py_hash_t. This is a signed integer the same size
as Py_ssize_t.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_HashNotImplemented">
Py_hash_t <tt class="descname">PyObject_HashNotImplemented</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_HashNotImplemented" title="Permalink to this definition">¶</a></dt>
<dd><p>Set a <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><tt class="xref py py-exc docutils literal"><span class="pre">TypeError</span></tt></a> indicating that <tt class="docutils literal"><span class="pre">type(o)</span></tt> is not hashable and return <tt class="docutils literal"><span class="pre">-1</span></tt>.
This function receives special treatment when stored in a <tt class="docutils literal"><span class="pre">tp_hash</span></tt> slot,
allowing a type to explicitly indicate to the interpreter that it is not
hashable.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_IsTrue">
int <tt class="descname">PyObject_IsTrue</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_IsTrue" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <tt class="docutils literal"><span class="pre">1</span></tt> if the object <em>o</em> is considered to be true, and <tt class="docutils literal"><span class="pre">0</span></tt> otherwise.
This is equivalent to the Python expression <tt class="docutils literal"><span class="pre">not</span> <span class="pre">not</span> <span class="pre">o</span></tt>. On failure, return
<tt class="docutils literal"><span class="pre">-1</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Not">
int <tt class="descname">PyObject_Not</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Not" title="Permalink to this definition">¶</a></dt>
<dd><p>Returns <tt class="docutils literal"><span class="pre">0</span></tt> if the object <em>o</em> is considered to be true, and <tt class="docutils literal"><span class="pre">1</span></tt> otherwise.
This is equivalent to the Python expression <tt class="docutils literal"><span class="pre">not</span> <span class="pre">o</span></tt>. On failure, return
<tt class="docutils literal"><span class="pre">-1</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Type">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_Type</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Type" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p id="index-5">When <em>o</em> is non-<em>NULL</em>, returns a type object corresponding to the object type
of object <em>o</em>. On failure, raises <a class="reference internal" href="../library/exceptions.html#SystemError" title="SystemError"><tt class="xref py py-exc docutils literal"><span class="pre">SystemError</span></tt></a> and returns <em>NULL</em>. This
is equivalent to the Python expression <tt class="docutils literal"><span class="pre">type(o)</span></tt>. This function increments the
reference count of the return value. There’s really no reason to use this
function instead of the common expression <tt class="docutils literal"><span class="pre">o->ob_type</span></tt>, which returns a
pointer of type <a class="reference internal" href="type.html#PyTypeObject" title="PyTypeObject"><tt class="xref c c-type docutils literal"><span class="pre">PyTypeObject*</span></tt></a>, except when the incremented reference
count is needed.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_TypeCheck">
int <tt class="descname">PyObject_TypeCheck</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="type.html#PyTypeObject" title="PyTypeObject">PyTypeObject</a><em> *type</em><big>)</big><a class="headerlink" href="#PyObject_TypeCheck" title="Permalink to this definition">¶</a></dt>
<dd><p>Return true if the object <em>o</em> is of type <em>type</em> or a subtype of <em>type</em>. Both
parameters must be non-<em>NULL</em>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Length">
Py_ssize_t <tt class="descname">PyObject_Length</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Length" title="Permalink to this definition">¶</a></dt>
<dt id="PyObject_Size">
Py_ssize_t <tt class="descname">PyObject_Size</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Size" title="Permalink to this definition">¶</a></dt>
<dd><p id="index-6">Return the length of object <em>o</em>. If the object <em>o</em> provides either the sequence
and mapping protocols, the sequence length is returned. On error, <tt class="docutils literal"><span class="pre">-1</span></tt> is
returned. This is the equivalent to the Python expression <tt class="docutils literal"><span class="pre">len(o)</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_GetItem">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_GetItem</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em><big>)</big><a class="headerlink" href="#PyObject_GetItem" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Return element of <em>o</em> corresponding to the object <em>key</em> or <em>NULL</em> on failure.
This is the equivalent of the Python expression <tt class="docutils literal"><span class="pre">o[key]</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_SetItem">
int <tt class="descname">PyObject_SetItem</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *v</em><big>)</big><a class="headerlink" href="#PyObject_SetItem" title="Permalink to this definition">¶</a></dt>
<dd><p>Map the object <em>key</em> to the value <em>v</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on failure. This is the
equivalent of the Python statement <tt class="docutils literal"><span class="pre">o[key]</span> <span class="pre">=</span> <span class="pre">v</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_DelItem">
int <tt class="descname">PyObject_DelItem</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em>, <a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *key</em><big>)</big><a class="headerlink" href="#PyObject_DelItem" title="Permalink to this definition">¶</a></dt>
<dd><p>Delete the mapping for <em>key</em> from <em>o</em>. Returns <tt class="docutils literal"><span class="pre">-1</span></tt> on failure. This is the
equivalent of the Python statement <tt class="docutils literal"><span class="pre">del</span> <span class="pre">o[key]</span></tt>.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_Dir">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_Dir</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_Dir" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>This is equivalent to the Python expression <tt class="docutils literal"><span class="pre">dir(o)</span></tt>, returning a (possibly
empty) list of strings appropriate for the object argument, or <em>NULL</em> if there
was an error. If the argument is <em>NULL</em>, this is like the Python <tt class="docutils literal"><span class="pre">dir()</span></tt>,
returning the names of the current locals; in this case, if no execution frame
is active then <em>NULL</em> is returned but <a class="reference internal" href="exceptions.html#PyErr_Occurred" title="PyErr_Occurred"><tt class="xref c c-func docutils literal"><span class="pre">PyErr_Occurred()</span></tt></a> will return false.</p>
</dd></dl>
<dl class="function">
<dt id="PyObject_GetIter">
<a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a>* <tt class="descname">PyObject_GetIter</tt><big>(</big><a class="reference internal" href="structures.html#PyObject" title="PyObject">PyObject</a><em> *o</em><big>)</big><a class="headerlink" href="#PyObject_GetIter" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>This is equivalent to the Python expression <tt class="docutils literal"><span class="pre">iter(o)</span></tt>. It returns a new
iterator for the object argument, or the object itself if the object is already
an iterator. Raises <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><tt class="xref py py-exc docutils literal"><span class="pre">TypeError</span></tt></a> and returns <em>NULL</em> if the object cannot be
iterated.</p>
</dd></dl>
</div>
</div>
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contrib-backports
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by-pkgid
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files
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