Added some more info on PyModule_GetState doc.

Author: s3rius

Doc/c-api/module.rst

@@ -93,7 +93,11 @@ Module Objects
 .. c:function:: void* PyModule_GetState(PyObject *module)
 
    Return the "state" of the module, that is, a pointer to the block of memory
-   allocated at module creation time, or ``NULL``.  See
+   allocated at module creation time, or ``NULL``.
+
+   Takes a pointer to a modlue as an argument.
+
+   See
    :c:member:`PyModuleDef.m_size`.