Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Includes/cpython/function.pxd

+from cpython.ref cimport PyObject
+
+cdef extern from "Python.h":
+
+    ############################################################################
+    # 7.5.3 Function Objects
+    ############################################################################
+    # There are a few functions specific to Python functions.
+
+    # PyFunctionObject
+    #
+    # The C structure used for functions.
+
+    # PyTypeObject PyFunction_Type
+    #
+    # This is an instance of PyTypeObject and represents the Python
+    # function type. It is exposed to Python programmers as
+    # types.FunctionType.
+
+    bint PyFunction_Check(object o)
+    # Return true if o is a function object (has type
+    # PyFunction_Type). The parameter must not be NULL.
+
+    object PyFunction_New(object code, object globals)
+    # Return value: New reference.
+    # Return a new function object associated with the code object
+    # code. globals must be a dictionary with the global variables
+    # accessible to the function.
+    # The function's docstring, name and __module__ are retrieved from
+    # the code object, the argument defaults and closure are set to
+    # NULL.
+
+    PyObject* PyFunction_GetCode(object op) except? NULL
+    # Return value: Borrowed reference.
+    # Return the code object associated with the function object op.
+
+    PyObject* PyFunction_GetGlobals(object op) except? NULL
+    # Return value: Borrowed reference.
+    # Return the globals dictionary associated with the function object op.
+
+    PyObject* PyFunction_GetModule(object op) except? NULL
+    # Return value: Borrowed reference.
+    # Return the __module__ attribute of the function object op. This
+    # is normally a string containing the module name, but can be set
+    # to any other object by Python code.
+
+    PyObject* PyFunction_GetDefaults(object op) except? NULL
+    # Return value: Borrowed reference.
+    # Return the argument default values of the function object
+    # op. This can be a tuple of arguments or NULL.
+
+    int PyFunction_SetDefaults(object op, object defaults) except -1
+    # Set the argument default values for the function object
+    # op. defaults must be Py_None or a tuple.
+    # Raises SystemError and returns -1 on failure.
+
+    PyObject* PyFunction_GetClosure(object op) except? NULL
+    # Return value: Borrowed reference.
+    # Return the closure associated with the function object op. This
+    # can be NULL or a tuple of cell objects.
+
+    int PyFunction_SetClosure(object op, object closure) except -1
+    # Set the closure associated with the function object op. closure
+    # must be Py_None or a tuple of cell objects.
+    # Raises SystemError and returns -1 on failure.