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<div class="section" id="parsing-arguments-and-building-values">
<span id="arg-parsing"></span><h1>Parsing arguments and building values<a class="headerlink" href="#parsing-arguments-and-building-values" title="Permalink to this headline">¶</a></h1>
<p>These functions are useful when creating your own extensions functions and
methods. Additional information and examples are available in
<a class="reference external" href="../extending/index.html#extending-index"><em>Extending and Embedding the Python Interpreter</em></a>.</p>
<p>The first three of these functions described, <a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a>,
<a title="PyArg_ParseTupleAndKeywords" class="reference internal" href="#PyArg_ParseTupleAndKeywords"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTupleAndKeywords()</span></tt></a>, and <a title="PyArg_Parse" class="reference internal" href="#PyArg_Parse"><tt class="xref docutils literal"><span class="pre">PyArg_Parse()</span></tt></a>, all use <em>format
strings</em> which are used to tell the function about the expected arguments. The
format strings use the same syntax for each of these functions.</p>
<p>A format string consists of zero or more “format units.” A format unit
describes one Python object; it is usually a single character or a parenthesized
sequence of format units. With a few exceptions, a format unit that is not a
parenthesized sequence normally corresponds to a single address argument to
these functions. In the following description, the quoted form is the format
unit; the entry in (round) parentheses is the Python object type that matches
the format unit; and the entry in [square] brackets is the type of the C
variable(s) whose address should be passed.</p>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">s</span></tt> (string or Unicode object) [const char *]</dt>
<dd><p class="first">Convert a Python string or Unicode object to a C pointer to a character string.
You must not provide storage for the string itself; a pointer to an existing
string is stored into the character pointer variable whose address you pass.
The C string is NUL-terminated. The Python string must not contain embedded NUL
bytes; if it does, a <a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> exception is raised. Unicode objects are
converted to C strings using the default encoding. If this conversion fails, a
<a title="exceptions.UnicodeError" class="reference external" href="../library/exceptions.html#exceptions.UnicodeError"><tt class="xref docutils literal"><span class="pre">UnicodeError</span></tt></a> is raised.</p>
<p class="last">Starting with Python 2.5 the type of the length argument can be
controlled by defining the macro <tt class="xref docutils literal"><span class="pre">PY_SSIZE_T_CLEAN</span></tt> before
including <tt class="docutils literal"><span class="pre">Python.h</span></tt>. If the macro is defined, length is a
<tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt> rather than an int.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">s*</span></tt> (string, Unicode, or any buffer compatible object) [Py_buffer *]</dt>
<dd>This is similar to <tt class="docutils literal"><span class="pre">s</span></tt>, but the code fills a <a title="Py_buffer" class="reference external" href="buffer.html#Py_buffer"><tt class="xref docutils literal"><span class="pre">Py_buffer</span></tt></a> structure
provided by the caller. In this case the Python string may contain embedded
null bytes. Unicode objects pass back a pointer to the default encoded
string version of the object if such a conversion is possible. The
underlying buffer is locked, so that the caller can subsequently use the
buffer even inside a <tt class="docutils literal"><span class="pre">Py_BEGIN_ALLOW_THREADS</span></tt> block. <strong>The caller is
responsible</strong> for calling <tt class="docutils literal"><span class="pre">PyBuffer_Release</span></tt> with the structure after it
has processed the data.</dd>
<dt><tt class="docutils literal"><span class="pre">s#</span></tt> (string, Unicode or any read buffer compatible object) [const char *, int or <tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt>]</dt>
<dd><p class="first">This variant on <tt class="docutils literal"><span class="pre">s</span></tt> stores into two C variables, the first one a pointer to
a character string, the second one its length. In this case the Python
string may contain embedded null bytes. Unicode objects pass back a pointer
to the default encoded string version of the object if such a conversion is
possible. All other read-buffer compatible objects pass back a reference to
the raw internal data representation. Since this format doesn’t allow
writable buffer compatible objects like byte arrays, <tt class="docutils literal"><span class="pre">s*</span></tt> is to be
preferred.</p>
<p class="last">The type of the length argument (int or <tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt>) is controlled by
defining the macro <tt class="xref docutils literal"><span class="pre">PY_SSIZE_T_CLEAN</span></tt> before including
<tt class="docutils literal"><span class="pre">Python.h</span></tt>. If the macro was defined, length is a <tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt>
rather than an int. This behavior will change in a future Python version to
only support <tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt> and drop int support. It is best to always
define <tt class="xref docutils literal"><span class="pre">PY_SSIZE_T_CLEAN</span></tt>.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">y</span></tt> (bytes object) [const char *]</dt>
<dd>This variant on <tt class="docutils literal"><span class="pre">s</span></tt> converts a Python bytes or bytearray object to a C
pointer to a character string. The bytes object must not contain embedded
NUL bytes; if it does, a <a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> exception is raised.</dd>
<dt><tt class="docutils literal"><span class="pre">y*</span></tt> (bytes object) [Py_buffer *]</dt>
<dd>This is to <tt class="docutils literal"><span class="pre">s*</span></tt> as <tt class="docutils literal"><span class="pre">y</span></tt> is to <tt class="docutils literal"><span class="pre">s</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">y#</span></tt> (bytes object) [const char *, int]</dt>
<dd>This variant on <tt class="docutils literal"><span class="pre">s#</span></tt> stores into two C variables, the first one a pointer
to a character string, the second one its length. This only accepts bytes
objects, no byte arrays.</dd>
<dt><tt class="docutils literal"><span class="pre">z</span></tt> (string or <tt class="xref docutils literal"><span class="pre">None</span></tt>) [const char *]</dt>
<dd>Like <tt class="docutils literal"><span class="pre">s</span></tt>, but the Python object may also be <tt class="xref docutils literal"><span class="pre">None</span></tt>, in which case the C
pointer is set to <em>NULL</em>.</dd>
<dt><tt class="docutils literal"><span class="pre">z*</span></tt> (string or <tt class="xref docutils literal"><span class="pre">None</span></tt> or any buffer compatible object) [Py_buffer*]</dt>
<dd>This is to <tt class="docutils literal"><span class="pre">s*</span></tt> as <tt class="docutils literal"><span class="pre">z</span></tt> is to <tt class="docutils literal"><span class="pre">s</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">z#</span></tt> (string or <tt class="xref docutils literal"><span class="pre">None</span></tt> or any read buffer compatible object) [const char *, int]</dt>
<dd>This is to <tt class="docutils literal"><span class="pre">s#</span></tt> as <tt class="docutils literal"><span class="pre">z</span></tt> is to <tt class="docutils literal"><span class="pre">s</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">u</span></tt> (Unicode object) [Py_UNICODE *]</dt>
<dd>Convert a Python Unicode object to a C pointer to a NUL-terminated buffer of
16-bit Unicode (UTF-16) data. As with <tt class="docutils literal"><span class="pre">s</span></tt>, there is no need to provide
storage for the Unicode data buffer; a pointer to the existing Unicode data is
stored into the <a title="Py_UNICODE" class="reference external" href="unicode.html#Py_UNICODE"><tt class="xref docutils literal"><span class="pre">Py_UNICODE</span></tt></a> pointer variable whose address you pass.</dd>
<dt><tt class="docutils literal"><span class="pre">u#</span></tt> (Unicode object) [Py_UNICODE *, int]</dt>
<dd>This variant on <tt class="docutils literal"><span class="pre">u</span></tt> stores into two C variables, the first one a pointer to a
Unicode data buffer, the second one its length. Non-Unicode objects are handled
by interpreting their read-buffer pointer as pointer to a <a title="Py_UNICODE" class="reference external" href="unicode.html#Py_UNICODE"><tt class="xref docutils literal"><span class="pre">Py_UNICODE</span></tt></a>
array.</dd>
<dt><tt class="docutils literal"><span class="pre">Z</span></tt> (Unicode or <tt class="xref docutils literal"><span class="pre">None</span></tt>) [Py_UNICODE *]</dt>
<dd>Like <tt class="docutils literal"><span class="pre">s</span></tt>, but the Python object may also be <tt class="xref docutils literal"><span class="pre">None</span></tt>, in which case the C
pointer is set to <em>NULL</em>.</dd>
<dt><tt class="docutils literal"><span class="pre">Z#</span></tt> (Unicode or <tt class="xref docutils literal"><span class="pre">None</span></tt>) [Py_UNICODE *, int]</dt>
<dd>This is to <tt class="docutils literal"><span class="pre">u#</span></tt> as <tt class="docutils literal"><span class="pre">Z</span></tt> is to <tt class="docutils literal"><span class="pre">u</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">es</span></tt> (string, Unicode object or character buffer compatible object) [const char *encoding, char **buffer]</dt>
<dd><p class="first">This variant on <tt class="docutils literal"><span class="pre">s</span></tt> is used for encoding Unicode and objects convertible to
Unicode into a character buffer. It only works for encoded data without embedded
NUL bytes.</p>
<p>This format requires two arguments. The first is only used as input, and
must be a <tt class="xref docutils literal"><span class="pre">const</span> <span class="pre">char*</span></tt> which points to the name of an encoding as a
NUL-terminated string, or <em>NULL</em>, in which case the default encoding is used.
An exception is raised if the named encoding is not known to Python. The
second argument must be a <tt class="xref docutils literal"><span class="pre">char**</span></tt>; the value of the pointer it
references will be set to a buffer with the contents of the argument text.
The text will be encoded in the encoding specified by the first argument.</p>
<p class="last"><a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a> will allocate a buffer of the needed size, copy the
encoded data into this buffer and adjust <em>*buffer</em> to reference the newly
allocated storage. The caller is responsible for calling <a title="PyMem_Free" class="reference external" href="memory.html#PyMem_Free"><tt class="xref docutils literal"><span class="pre">PyMem_Free()</span></tt></a> to
free the allocated buffer after use.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">et</span></tt> (string, Unicode object or character buffer compatible object) [const char *encoding, char **buffer]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">es</span></tt> except that 8-bit string objects are passed through without
recoding them. Instead, the implementation assumes that the string object uses
the encoding passed in as parameter.</dd>
<dt><tt class="docutils literal"><span class="pre">es#</span></tt> (string, Unicode object or character buffer compatible object) [const char *encoding, char **buffer, int *buffer_length]</dt>
<dd><p class="first">This variant on <tt class="docutils literal"><span class="pre">s#</span></tt> is used for encoding Unicode and objects convertible to
Unicode into a character buffer. Unlike the <tt class="docutils literal"><span class="pre">es</span></tt> format, this variant allows
input data which contains NUL characters.</p>
<p>It requires three arguments. The first is only used as input, and must be a
<tt class="xref docutils literal"><span class="pre">const</span> <span class="pre">char*</span></tt> which points to the name of an encoding as a
NUL-terminated string, or <em>NULL</em>, in which case the default encoding is used.
An exception is raised if the named encoding is not known to Python. The
second argument must be a <tt class="xref docutils literal"><span class="pre">char**</span></tt>; the value of the pointer it
references will be set to a buffer with the contents of the argument text.
The text will be encoded in the encoding specified by the first argument.
The third argument must be a pointer to an integer; the referenced integer
will be set to the number of bytes in the output buffer.</p>
<p>There are two modes of operation:</p>
<p>If <em>*buffer</em> points a <em>NULL</em> pointer, the function will allocate a buffer of
the needed size, copy the encoded data into this buffer and set <em>*buffer</em> to
reference the newly allocated storage. The caller is responsible for calling
<a title="PyMem_Free" class="reference external" href="memory.html#PyMem_Free"><tt class="xref docutils literal"><span class="pre">PyMem_Free()</span></tt></a> to free the allocated buffer after usage.</p>
<p>If <em>*buffer</em> points to a non-<em>NULL</em> pointer (an already allocated buffer),
<a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a> will use this location as the buffer and interpret the
initial value of <em>*buffer_length</em> as the buffer size. It will then copy the
encoded data into the buffer and NUL-terminate it. If the buffer is not large
enough, a <a title="exceptions.ValueError" class="reference external" href="../library/exceptions.html#exceptions.ValueError"><tt class="xref docutils literal"><span class="pre">ValueError</span></tt></a> will be set.</p>
<p class="last">In both cases, <em>*buffer_length</em> is set to the length of the encoded data
without the trailing NUL byte.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">et#</span></tt> (string, Unicode object or character buffer compatible object) [const char *encoding, char **buffer, int *buffer_length]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">es#</span></tt> except that string objects are passed through without recoding
them. Instead, the implementation assumes that the string object uses the
encoding passed in as parameter.</dd>
<dt><tt class="docutils literal"><span class="pre">b</span></tt> (integer) [unsigned char]</dt>
<dd>Convert a nonnegative Python integer to an unsigned tiny int, stored in a C
<tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">char</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">B</span></tt> (integer) [unsigned char]</dt>
<dd>Convert a Python integer to a tiny int without overflow checking, stored in a C
<tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">char</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">h</span></tt> (integer) [short int]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">short</span> <span class="pre">int</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">H</span></tt> (integer) [unsigned short int]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">short</span> <span class="pre">int</span></tt>, without overflow
checking.</dd>
<dt><tt class="docutils literal"><span class="pre">i</span></tt> (integer) [int]</dt>
<dd>Convert a Python integer to a plain C <tt class="xref docutils literal"><span class="pre">int</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">I</span></tt> (integer) [unsigned int]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">int</span></tt>, without overflow
checking.</dd>
<dt><tt class="docutils literal"><span class="pre">l</span></tt> (integer) [long int]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">long</span> <span class="pre">int</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">k</span></tt> (integer) [unsigned long]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">long</span></tt> without
overflow checking.</dd>
<dt><tt class="docutils literal"><span class="pre">L</span></tt> (integer) [PY_LONG_LONG]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">long</span> <span class="pre">long</span></tt>. This format is only
available on platforms that support <tt class="xref docutils literal"><span class="pre">long</span> <span class="pre">long</span></tt> (or <tt class="xref docutils literal"><span class="pre">_int64</span></tt> on
Windows).</dd>
<dt><tt class="docutils literal"><span class="pre">K</span></tt> (integer) [unsigned PY_LONG_LONG]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">long</span> <span class="pre">long</span></tt>
without overflow checking. This format is only available on platforms that
support <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">long</span> <span class="pre">long</span></tt> (or <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">_int64</span></tt> on Windows).</dd>
<dt><tt class="docutils literal"><span class="pre">n</span></tt> (integer) [Py_ssize_t]</dt>
<dd>Convert a Python integer to a C <tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">c</span></tt> (string of length 1) [char]</dt>
<dd>Convert a Python character, represented as a byte string of length 1, to a C
<tt class="xref docutils literal"><span class="pre">char</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">C</span></tt> (string of length 1) [int]</dt>
<dd>Convert a Python character, represented as a unicode string of length 1, to a
C <tt class="xref docutils literal"><span class="pre">int</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">f</span></tt> (float) [float]</dt>
<dd>Convert a Python floating point number to a C <tt class="xref docutils literal"><span class="pre">float</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">d</span></tt> (float) [double]</dt>
<dd>Convert a Python floating point number to a C <tt class="xref docutils literal"><span class="pre">double</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">D</span></tt> (complex) [Py_complex]</dt>
<dd>Convert a Python complex number to a C <a title="Py_complex" class="reference external" href="complex.html#Py_complex"><tt class="xref docutils literal"><span class="pre">Py_complex</span></tt></a> structure.</dd>
<dt><tt class="docutils literal"><span class="pre">O</span></tt> (object) [PyObject *]</dt>
<dd>Store a Python object (without any conversion) in a C object pointer. The C
program thus receives the actual object that was passed. The object’s reference
count is not increased. The pointer stored is not <em>NULL</em>.</dd>
<dt><tt class="docutils literal"><span class="pre">O!</span></tt> (object) [<em>typeobject</em>, PyObject *]</dt>
<dd>Store a Python object in a C object pointer. This is similar to <tt class="docutils literal"><span class="pre">O</span></tt>, but
takes two C arguments: the first is the address of a Python type object, the
second is the address of the C variable (of type <a title="PyObject" class="reference external" href="structures.html#PyObject"><tt class="xref docutils literal"><span class="pre">PyObject*</span></tt></a>) into which
the object pointer is stored. If the Python object does not have the required
type, <a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> is raised.</dd>
<dt><tt class="docutils literal"><span class="pre">O&</span></tt> (object) [<em>converter</em>, <em>anything</em>]</dt>
<dd><p class="first">Convert a Python object to a C variable through a <em>converter</em> function. This
takes two arguments: the first is a function, the second is the address of a C
variable (of arbitrary type), converted to <tt class="xref docutils literal"><span class="pre">void</span> <span class="pre">*</span></tt>. The <em>converter</em>
function in turn is called as follows:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="n">status</span> <span class="o">=</span> <span class="n">converter</span><span class="p">(</span><span class="n">object</span><span class="p">,</span> <span class="n">address</span><span class="p">);</span>
</pre></div>
</div>
<p>where <em>object</em> is the Python object to be converted and <em>address</em> is the
<tt class="xref docutils literal"><span class="pre">void*</span></tt> argument that was passed to the <a title="PyArg_Parse" class="reference internal" href="#PyArg_Parse"><tt class="xref docutils literal"><span class="pre">PyArg_Parse*()</span></tt></a> function.
The returned <em>status</em> should be <tt class="docutils literal"><span class="pre">1</span></tt> for a successful conversion and <tt class="docutils literal"><span class="pre">0</span></tt> if
the conversion has failed. When the conversion fails, the <em>converter</em> function
should raise an exception and leave the content of <em>address</em> unmodified.</p>
<p>If the <em>converter</em> returns Py_CLEANUP_SUPPORTED, it may get called a second time
if the argument parsing eventually fails, giving the converter a chance to release
any memory that it had already allocated. In this second call, the <em>object</em> parameter
will be NULL; <em>address</em> will have the same value as in the original call.</p>
<p class="last">
<span class="versionmodified">Changed in version 3.1: </span>Py_CLEANUP_SUPPORTED was added.</p>
</dd>
<dt><tt class="docutils literal"><span class="pre">S</span></tt> (string) [PyStringObject *]</dt>
<dd>Like <tt class="docutils literal"><span class="pre">O</span></tt> but requires that the Python object is a string object. Raises
<a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> if the object is not a string object. The C variable may also
be declared as <a title="PyObject" class="reference external" href="structures.html#PyObject"><tt class="xref docutils literal"><span class="pre">PyObject*</span></tt></a>.</dd>
<dt><tt class="docutils literal"><span class="pre">U</span></tt> (Unicode string) [PyUnicodeObject *]</dt>
<dd>Like <tt class="docutils literal"><span class="pre">O</span></tt> but requires that the Python object is a Unicode object. Raises
<a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> if the object is not a Unicode object. The C variable may also
be declared as <a title="PyObject" class="reference external" href="structures.html#PyObject"><tt class="xref docutils literal"><span class="pre">PyObject*</span></tt></a>.</dd>
<dt><tt class="docutils literal"><span class="pre">t#</span></tt> (read-only character buffer) [char *, int]</dt>
<dd>Like <tt class="docutils literal"><span class="pre">s#</span></tt>, but accepts any object which implements the read-only buffer
interface. The <tt class="xref docutils literal"><span class="pre">char*</span></tt> variable is set to point to the first byte of
the buffer, and the <tt class="xref docutils literal"><span class="pre">int</span></tt> is set to the length of the buffer. Only
single-segment buffer objects are accepted; <a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> is raised for all
others.</dd>
<dt><tt class="docutils literal"><span class="pre">w</span></tt> (read-write character buffer) [char *]</dt>
<dd>Similar to <tt class="docutils literal"><span class="pre">s</span></tt>, but accepts any object which implements the read-write buffer
interface. The caller must determine the length of the buffer by other means,
or use <tt class="docutils literal"><span class="pre">w#</span></tt> instead. Only single-segment buffer objects are accepted;
<a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> is raised for all others.</dd>
<dt><tt class="docutils literal"><span class="pre">w*</span></tt> (read-write byte-oriented buffer) [Py_buffer *]</dt>
<dd>This is to <tt class="docutils literal"><span class="pre">w</span></tt> what <tt class="docutils literal"><span class="pre">s*</span></tt> is to <tt class="docutils literal"><span class="pre">s</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">w#</span></tt> (read-write character buffer) [char *, int]</dt>
<dd>Like <tt class="docutils literal"><span class="pre">s#</span></tt>, but accepts any object which implements the read-write buffer
interface. The <tt class="xref docutils literal"><span class="pre">char</span> <span class="pre">*</span></tt> variable is set to point to the first byte
of the buffer, and the <tt class="xref docutils literal"><span class="pre">int</span></tt> is set to the length of the buffer.
Only single-segment buffer objects are accepted; <a title="exceptions.TypeError" class="reference external" href="../library/exceptions.html#exceptions.TypeError"><tt class="xref docutils literal"><span class="pre">TypeError</span></tt></a> is raised
for all others.</dd>
<dt><tt class="docutils literal"><span class="pre">(items)</span></tt> (tuple) [<em>matching-items</em>]</dt>
<dd>The object must be a Python sequence whose length is the number of format units
in <em>items</em>. The C arguments must correspond to the individual format units in
<em>items</em>. Format units for sequences may be nested.</dd>
</dl>
<p>It is possible to pass “long” integers (integers whose value exceeds the
platform’s <tt class="xref docutils literal"><span class="pre">LONG_MAX</span></tt>) however no proper range checking is done — the
most significant bits are silently truncated when the receiving field is too
small to receive the value (actually, the semantics are inherited from downcasts
in C — your mileage may vary).</p>
<p>A few other characters have a meaning in a format string. These may not occur
inside nested parentheses. They are:</p>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">|</span></tt></dt>
<dd>Indicates that the remaining arguments in the Python argument list are optional.
The C variables corresponding to optional arguments should be initialized to
their default value — when an optional argument is not specified,
<a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a> does not touch the contents of the corresponding C
variable(s).</dd>
<dt><tt class="docutils literal"><span class="pre">:</span></tt></dt>
<dd>The list of format units ends here; the string after the colon is used as the
function name in error messages (the “associated value” of the exception that
<a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a> raises).</dd>
<dt><tt class="docutils literal"><span class="pre">;</span></tt></dt>
<dd>The list of format units ends here; the string after the semicolon is used as
the error message <em>instead</em> of the default error message. <tt class="docutils literal"><span class="pre">:</span></tt> and <tt class="docutils literal"><span class="pre">;</span></tt>
mutually exclude each other.</dd>
</dl>
<p>Note that any Python object references which are provided to the caller are
<em>borrowed</em> references; do not decrement their reference count!</p>
<p>Additional arguments passed to these functions must be addresses of variables
whose type is determined by the format string; these are used to store values
from the input tuple. There are a few cases, as described in the list of format
units above, where these parameters are used as input values; they should match
what is specified for the corresponding format unit in that case.</p>
<p>For the conversion to succeed, the <em>arg</em> object must match the format
and the format must be exhausted. On success, the
<a title="PyArg_Parse" class="reference internal" href="#PyArg_Parse"><tt class="xref docutils literal"><span class="pre">PyArg_Parse*()</span></tt></a> functions return true, otherwise they return
false and raise an appropriate exception. When the
<a title="PyArg_Parse" class="reference internal" href="#PyArg_Parse"><tt class="xref docutils literal"><span class="pre">PyArg_Parse*()</span></tt></a> functions fail due to conversion failure in one
of the format units, the variables at the addresses corresponding to that
and the following format units are left untouched.</p>
<dl class="cfunction">
<dt id="PyArg_ParseTuple">
int <tt class="descname">PyArg_ParseTuple</tt><big>(</big><a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *args</em>, const char<em> *format</em>, ...<big>)</big><a class="headerlink" href="#PyArg_ParseTuple" title="Permalink to this definition">¶</a></dt>
<dd>Parse the parameters of a function that takes only positional parameters into
local variables. Returns true on success; on failure, it returns false and
raises the appropriate exception.</dd></dl>
<dl class="cfunction">
<dt id="PyArg_VaParse">
int <tt class="descname">PyArg_VaParse</tt><big>(</big><a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *args</em>, const char<em> *format</em>, va_list<em> vargs</em><big>)</big><a class="headerlink" href="#PyArg_VaParse" title="Permalink to this definition">¶</a></dt>
<dd>Identical to <a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a>, except that it accepts a va_list rather
than a variable number of arguments.</dd></dl>
<dl class="cfunction">
<dt id="PyArg_ParseTupleAndKeywords">
int <tt class="descname">PyArg_ParseTupleAndKeywords</tt><big>(</big><a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *args</em>, <a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *kw</em>, const char<em> *format</em>, char<em> *keywords[]</em>, ...<big>)</big><a class="headerlink" href="#PyArg_ParseTupleAndKeywords" title="Permalink to this definition">¶</a></dt>
<dd>Parse the parameters of a function that takes both positional and keyword
parameters into local variables. Returns true on success; on failure, it
returns false and raises the appropriate exception.</dd></dl>
<dl class="cfunction">
<dt id="PyArg_VaParseTupleAndKeywords">
int <tt class="descname">PyArg_VaParseTupleAndKeywords</tt><big>(</big><a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *args</em>, <a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *kw</em>, const char<em> *format</em>, char<em> *keywords[]</em>, va_list<em> vargs</em><big>)</big><a class="headerlink" href="#PyArg_VaParseTupleAndKeywords" title="Permalink to this definition">¶</a></dt>
<dd>Identical to <a title="PyArg_ParseTupleAndKeywords" class="reference internal" href="#PyArg_ParseTupleAndKeywords"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTupleAndKeywords()</span></tt></a>, except that it accepts a
va_list rather than a variable number of arguments.</dd></dl>
<dl class="cfunction">
<dt id="PyArg_Parse">
int <tt class="descname">PyArg_Parse</tt><big>(</big><a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *args</em>, const char<em> *format</em>, ...<big>)</big><a class="headerlink" href="#PyArg_Parse" title="Permalink to this definition">¶</a></dt>
<dd>Function used to deconstruct the argument lists of “old-style” functions —
these are functions which use the <tt class="xref docutils literal"><span class="pre">METH_OLDARGS</span></tt> parameter parsing
method. This is not recommended for use in parameter parsing in new code, and
most code in the standard interpreter has been modified to no longer use this
for that purpose. It does remain a convenient way to decompose other tuples,
however, and may continue to be used for that purpose.</dd></dl>
<dl class="cfunction">
<dt id="PyArg_UnpackTuple">
int <tt class="descname">PyArg_UnpackTuple</tt><big>(</big><a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a><em> *args</em>, const char<em> *name</em>, Py_ssize_t<em> min</em>, Py_ssize_t<em> max</em>, ...<big>)</big><a class="headerlink" href="#PyArg_UnpackTuple" title="Permalink to this definition">¶</a></dt>
<dd><p>A simpler form of parameter retrieval which does not use a format string to
specify the types of the arguments. Functions which use this method to retrieve
their parameters should be declared as <a title="METH_VARARGS" class="reference external" href="structures.html#METH_VARARGS"><tt class="xref docutils literal"><span class="pre">METH_VARARGS</span></tt></a> in function or
method tables. The tuple containing the actual parameters should be passed as
<em>args</em>; it must actually be a tuple. The length of the tuple must be at least
<em>min</em> and no more than <em>max</em>; <em>min</em> and <em>max</em> may be equal. Additional
arguments must be passed to the function, each of which should be a pointer to a
<a title="PyObject" class="reference external" href="structures.html#PyObject"><tt class="xref docutils literal"><span class="pre">PyObject*</span></tt></a> variable; these will be filled in with the values from
<em>args</em>; they will contain borrowed references. The variables which correspond
to optional parameters not given by <em>args</em> will not be filled in; these should
be initialized by the caller. This function returns true on success and false if
<em>args</em> is not a tuple or contains the wrong number of elements; an exception
will be set if there was a failure.</p>
<p>This is an example of the use of this function, taken from the sources for the
<tt class="xref docutils literal"><span class="pre">_weakref</span></tt> helper module for weak references:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="k">static</span> <span class="n">PyObject</span> <span class="o">*</span>
<span class="nf">weakref_ref</span><span class="p">(</span><span class="n">PyObject</span> <span class="o">*</span><span class="n">self</span><span class="p">,</span> <span class="n">PyObject</span> <span class="o">*</span><span class="n">args</span><span class="p">)</span>
<span class="p">{</span>
<span class="n">PyObject</span> <span class="o">*</span><span class="n">object</span><span class="p">;</span>
<span class="n">PyObject</span> <span class="o">*</span><span class="n">callback</span> <span class="o">=</span> <span class="nb">NULL</span><span class="p">;</span>
<span class="n">PyObject</span> <span class="o">*</span><span class="n">result</span> <span class="o">=</span> <span class="nb">NULL</span><span class="p">;</span>
<span class="k">if</span> <span class="p">(</span><span class="n">PyArg_UnpackTuple</span><span class="p">(</span><span class="n">args</span><span class="p">,</span> <span class="s">"ref"</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="o">&</span><span class="n">object</span><span class="p">,</span> <span class="o">&</span><span class="n">callback</span><span class="p">))</span> <span class="p">{</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">PyWeakref_NewRef</span><span class="p">(</span><span class="n">object</span><span class="p">,</span> <span class="n">callback</span><span class="p">);</span>
<span class="p">}</span>
<span class="k">return</span> <span class="n">result</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p>The call to <a title="PyArg_UnpackTuple" class="reference internal" href="#PyArg_UnpackTuple"><tt class="xref docutils literal"><span class="pre">PyArg_UnpackTuple()</span></tt></a> in this example is entirely equivalent to
this call to <a title="PyArg_ParseTuple" class="reference internal" href="#PyArg_ParseTuple"><tt class="xref docutils literal"><span class="pre">PyArg_ParseTuple()</span></tt></a>:</p>
<div class="highlight-c"><div class="highlight"><pre><span class="n">PyArg_ParseTuple</span><span class="p">(</span><span class="n">args</span><span class="p">,</span> <span class="s">"O|O:ref"</span><span class="p">,</span> <span class="o">&</span><span class="n">object</span><span class="p">,</span> <span class="o">&</span><span class="n">callback</span><span class="p">)</span>
</pre></div>
</div>
</dd></dl>
<dl class="cfunction">
<dt id="Py_BuildValue">
<a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a>* <tt class="descname">Py_BuildValue</tt><big>(</big>const char<em> *format</em>, ...<big>)</big><a class="headerlink" href="#Py_BuildValue" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Create a new value based on a format string similar to those accepted by the
<a title="PyArg_Parse" class="reference internal" href="#PyArg_Parse"><tt class="xref docutils literal"><span class="pre">PyArg_Parse*()</span></tt></a> family of functions and a sequence of values. Returns
the value or <em>NULL</em> in the case of an error; an exception will be raised if
<em>NULL</em> is returned.</p>
<p><a title="Py_BuildValue" class="reference internal" href="#Py_BuildValue"><tt class="xref docutils literal"><span class="pre">Py_BuildValue()</span></tt></a> does not always build a tuple. It builds a tuple only if
its format string contains two or more format units. If the format string is
empty, it returns <tt class="xref docutils literal"><span class="pre">None</span></tt>; if it contains exactly one format unit, it returns
whatever object is described by that format unit. To force it to return a tuple
of size 0 or one, parenthesize the format string.</p>
<p>When memory buffers are passed as parameters to supply data to build objects, as
for the <tt class="docutils literal"><span class="pre">s</span></tt> and <tt class="docutils literal"><span class="pre">s#</span></tt> formats, the required data is copied. Buffers provided
by the caller are never referenced by the objects created by
<a title="Py_BuildValue" class="reference internal" href="#Py_BuildValue"><tt class="xref docutils literal"><span class="pre">Py_BuildValue()</span></tt></a>. In other words, if your code invokes <tt class="xref docutils literal"><span class="pre">malloc()</span></tt>
and passes the allocated memory to <a title="Py_BuildValue" class="reference internal" href="#Py_BuildValue"><tt class="xref docutils literal"><span class="pre">Py_BuildValue()</span></tt></a>, your code is
responsible for calling <tt class="xref docutils literal"><span class="pre">free()</span></tt> for that memory once
<a title="Py_BuildValue" class="reference internal" href="#Py_BuildValue"><tt class="xref docutils literal"><span class="pre">Py_BuildValue()</span></tt></a> returns.</p>
<p>In the following description, the quoted form is the format unit; the entry in
(round) parentheses is the Python object type that the format unit will return;
and the entry in [square] brackets is the type of the C value(s) to be passed.</p>
<p>The characters space, tab, colon and comma are ignored in format strings (but
not within format units such as <tt class="docutils literal"><span class="pre">s#</span></tt>). This can be used to make long format
strings a tad more readable.</p>
<dl class="docutils">
<dt><tt class="docutils literal"><span class="pre">s</span></tt> (string) [char *]</dt>
<dd>Convert a null-terminated C string to a Python object. If the C string pointer
is <em>NULL</em>, <tt class="xref docutils literal"><span class="pre">None</span></tt> is used.</dd>
<dt><tt class="docutils literal"><span class="pre">s#</span></tt> (string) [char *, int]</dt>
<dd>Convert a C string and its length to a Python object. If the C string pointer
is <em>NULL</em>, the length is ignored and <tt class="xref docutils literal"><span class="pre">None</span></tt> is returned.</dd>
<dt><tt class="docutils literal"><span class="pre">y</span></tt> (bytes) [char *]</dt>
<dd>This converts a C string to a Python <a title="bytes" class="reference external" href="../library/functions.html#bytes"><tt class="xref docutils literal"><span class="pre">bytes()</span></tt></a> object. If the C
string pointer is <em>NULL</em>, <tt class="xref docutils literal"><span class="pre">None</span></tt> is returned.</dd>
<dt><tt class="docutils literal"><span class="pre">y#</span></tt> (bytes) [char *, int]</dt>
<dd>This converts a C string and its lengths to a Python object. If the C
string pointer is <em>NULL</em>, <tt class="xref docutils literal"><span class="pre">None</span></tt> is returned.</dd>
<dt><tt class="docutils literal"><span class="pre">z</span></tt> (string or <tt class="xref docutils literal"><span class="pre">None</span></tt>) [char *]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">s</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">z#</span></tt> (string or <tt class="xref docutils literal"><span class="pre">None</span></tt>) [char *, int]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">s#</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">u</span></tt> (Unicode string) [Py_UNICODE *]</dt>
<dd>Convert a null-terminated buffer of Unicode (UCS-2 or UCS-4) data to a Python
Unicode object. If the Unicode buffer pointer is <em>NULL</em>, <tt class="xref docutils literal"><span class="pre">None</span></tt> is returned.</dd>
<dt><tt class="docutils literal"><span class="pre">u#</span></tt> (Unicode string) [Py_UNICODE *, int]</dt>
<dd>Convert a Unicode (UCS-2 or UCS-4) data buffer and its length to a Python
Unicode object. If the Unicode buffer pointer is <em>NULL</em>, the length is ignored
and <tt class="xref docutils literal"><span class="pre">None</span></tt> is returned.</dd>
<dt><tt class="docutils literal"><span class="pre">U</span></tt> (string) [char *]</dt>
<dd>Convert a null-terminated C string to a Python unicode object. If the C string
pointer is <em>NULL</em>, <tt class="xref docutils literal"><span class="pre">None</span></tt> is used.</dd>
<dt><tt class="docutils literal"><span class="pre">U#</span></tt> (string) [char *, int]</dt>
<dd>Convert a C string and its length to a Python unicode object. If the C string
pointer is <em>NULL</em>, the length is ignored and <tt class="xref docutils literal"><span class="pre">None</span></tt> is returned.</dd>
<dt><tt class="docutils literal"><span class="pre">i</span></tt> (integer) [int]</dt>
<dd>Convert a plain C <tt class="xref docutils literal"><span class="pre">int</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">b</span></tt> (integer) [char]</dt>
<dd>Convert a plain C <tt class="xref docutils literal"><span class="pre">char</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">h</span></tt> (integer) [short int]</dt>
<dd>Convert a plain C <tt class="xref docutils literal"><span class="pre">short</span> <span class="pre">int</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">l</span></tt> (integer) [long int]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">long</span> <span class="pre">int</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">B</span></tt> (integer) [unsigned char]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">char</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">H</span></tt> (integer) [unsigned short int]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">short</span> <span class="pre">int</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">I</span></tt> (integer) [unsigned int]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">int</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">k</span></tt> (integer) [unsigned long]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">long</span></tt> to a Python integer object.</dd>
<dt><tt class="docutils literal"><span class="pre">L</span></tt> (long) [PY_LONG_LONG]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">long</span> <span class="pre">long</span></tt> to a Python integer object. Only available
on platforms that support <tt class="xref docutils literal"><span class="pre">long</span> <span class="pre">long</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">K</span></tt> (long) [unsigned PY_LONG_LONG]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">long</span> <span class="pre">long</span></tt> to a Python integer object. Only
available on platforms that support <tt class="xref docutils literal"><span class="pre">unsigned</span> <span class="pre">long</span> <span class="pre">long</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">n</span></tt> (int) [Py_ssize_t]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">Py_ssize_t</span></tt> to a Python integer.</dd>
<dt><tt class="docutils literal"><span class="pre">c</span></tt> (string of length 1) [char]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">int</span></tt> representing a byte to a Python byte string of
length 1.</dd>
<dt><tt class="docutils literal"><span class="pre">C</span></tt> (string of length 1) [int]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">int</span></tt> representing a character to Python unicode
string of length 1.</dd>
<dt><tt class="docutils literal"><span class="pre">d</span></tt> (float) [double]</dt>
<dd>Convert a C <tt class="xref docutils literal"><span class="pre">double</span></tt> to a Python floating point number.</dd>
<dt><tt class="docutils literal"><span class="pre">f</span></tt> (float) [float]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">d</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">D</span></tt> (complex) [Py_complex *]</dt>
<dd>Convert a C <a title="Py_complex" class="reference external" href="complex.html#Py_complex"><tt class="xref docutils literal"><span class="pre">Py_complex</span></tt></a> structure to a Python complex number.</dd>
<dt><tt class="docutils literal"><span class="pre">O</span></tt> (object) [PyObject *]</dt>
<dd>Pass a Python object untouched (except for its reference count, which is
incremented by one). If the object passed in is a <em>NULL</em> pointer, it is assumed
that this was caused because the call producing the argument found an error and
set an exception. Therefore, <a title="Py_BuildValue" class="reference internal" href="#Py_BuildValue"><tt class="xref docutils literal"><span class="pre">Py_BuildValue()</span></tt></a> will return <em>NULL</em> but won’t
raise an exception. If no exception has been raised yet, <a title="exceptions.SystemError" class="reference external" href="../library/exceptions.html#exceptions.SystemError"><tt class="xref docutils literal"><span class="pre">SystemError</span></tt></a> is
set.</dd>
<dt><tt class="docutils literal"><span class="pre">S</span></tt> (object) [PyObject *]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">O</span></tt>.</dd>
<dt><tt class="docutils literal"><span class="pre">N</span></tt> (object) [PyObject *]</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">O</span></tt>, except it doesn’t increment the reference count on the object.
Useful when the object is created by a call to an object constructor in the
argument list.</dd>
<dt><tt class="docutils literal"><span class="pre">O&</span></tt> (object) [<em>converter</em>, <em>anything</em>]</dt>
<dd>Convert <em>anything</em> to a Python object through a <em>converter</em> function. The
function is called with <em>anything</em> (which should be compatible with <tt class="xref docutils literal"><span class="pre">void</span>
<span class="pre">*</span></tt>) as its argument and should return a “new” Python object, or <em>NULL</em> if an
error occurred.</dd>
<dt><tt class="docutils literal"><span class="pre">(items)</span></tt> (tuple) [<em>matching-items</em>]</dt>
<dd>Convert a sequence of C values to a Python tuple with the same number of items.</dd>
<dt><tt class="docutils literal"><span class="pre">[items]</span></tt> (list) [<em>matching-items</em>]</dt>
<dd>Convert a sequence of C values to a Python list with the same number of items.</dd>
<dt><tt class="docutils literal"><span class="pre">{items}</span></tt> (dictionary) [<em>matching-items</em>]</dt>
<dd>Convert a sequence of C values to a Python dictionary. Each pair of consecutive
C values adds one item to the dictionary, serving as key and value,
respectively.</dd>
</dl>
<p>If there is an error in the format string, the <a title="exceptions.SystemError" class="reference external" href="../library/exceptions.html#exceptions.SystemError"><tt class="xref docutils literal"><span class="pre">SystemError</span></tt></a> exception is
set and <em>NULL</em> returned.</p>
</dd></dl>
<dl class="cfunction">
<dt id="Py_VaBuildValue">
<a title="PyObject" class="reference external" href="structures.html#PyObject">PyObject</a>* <tt class="descname">Py_VaBuildValue</tt><big>(</big>const char<em> *format</em>, va_list<em> vargs</em><big>)</big><a class="headerlink" href="#Py_VaBuildValue" title="Permalink to this definition">¶</a></dt>
<dd>Identical to <a title="Py_BuildValue" class="reference internal" href="#Py_BuildValue"><tt class="xref docutils literal"><span class="pre">Py_BuildValue()</span></tt></a>, except that it accepts a va_list
rather than a variable number of arguments.</dd></dl>
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