fix export of size_t parse stack function

Python/getargs.c

@@ -26,6 +26,8 @@ int _PyArg_VaParseTupleAndKeywordsFast(PyObject *, PyObject *,
 #ifdef HAVE_DECLSPEC_DLL
 /* Export functions */
 PyAPI_FUNC(int) _PyArg_Parse_SizeT(PyObject *, const char *, ...);
+PyAPI_FUNC(int) _PyArg_ParseStack_SizeT(PyObject **args, Py_ssize_t nargs, PyObject *kwnames,
+                                        struct _PyArg_Parser *parser, ...);
 PyAPI_FUNC(int) _PyArg_ParseTuple_SizeT(PyObject *, const char *, ...);
 PyAPI_FUNC(int) _PyArg_ParseTupleAndKeywords_SizeT(PyObject *, PyObject *,
                                                   const char *, char **, ...);