Py_InitModule4(): Accept NULL for the 'methods' argument. This makes

sense now that extension types can support __init__ directly rather
than requiring function constructors.

Python/modsupport.c

@@ -56,6 +56,7 @@ Py_InitModule4(char *name, PyMethodDef *methods, char *doc,
 	if ((m = PyImport_AddModule(name)) == NULL)
 		return NULL;
 	d = PyModule_GetDict(m);
+	if (methods != NULL) {
 		for (ml = methods; ml->ml_name != NULL; ml++) {
 			if ((ml->ml_flags & METH_CLASS) ||
 			    (ml->ml_flags & METH_STATIC)) {
@@ -73,6 +74,7 @@ Py_InitModule4(char *name, PyMethodDef *methods, char *doc,
 			}
 			Py_DECREF(v);
 		}
+	}
 	if (doc != NULL) {
 		v = PyString_FromString(doc);
 		if (v == NULL || PyDict_SetItemString(d, "__doc__", v) != 0) {