nest if for clarity

Python/ceval.c

@@ -3155,18 +3155,18 @@ PyEval_EvalCodeEx(PyCodeObject *co, PyObject *globals, PyObject *locals,
 		}
 		if (co->co_kwonlyargcount > 0) {
 			for (i = co->co_argcount; i < total_args; i++) {
-				PyObject *name, *def;
+				PyObject *name;
 				if (GETLOCAL(i) != NULL)
 					continue;
 				name = PyTuple_GET_ITEM(co->co_varnames, i);
-				def = NULL;
-				if (kwdefs != NULL)
-					def = PyDict_GetItem(kwdefs, name);
-				if (def != NULL) {
+				if (kwdefs != NULL) {
+					PyObject *def = PyDict_GetItem(kwdefs, name);
+					if (def) {
 						Py_INCREF(def);
 						SETLOCAL(i, def);
 						continue;
 					}
+				}
 				PyErr_Format(PyExc_TypeError,
 					"%U() needs keyword-only argument %S",
 					co->co_name, name);