bpo-36063: Minor performance tweak in long_divmod(). (GH-11915)

Objects/longobject.c

@@ -4103,8 +4103,8 @@ long_divmod(PyObject *a, PyObject *b)
     }
     z = PyTuple_New(2);
     if (z != NULL) {
-        PyTuple_SetItem(z, 0, (PyObject *) div);
-        PyTuple_SetItem(z, 1, (PyObject *) mod);
+        PyTuple_SET_ITEM(z, 0, (PyObject *) div);
+        PyTuple_SET_ITEM(z, 1, (PyObject *) mod);
     }
     else {
         Py_DECREF(div);