use PyType_GetSlot() when using the fallback

Author: neonene

Objects/typeobject.c

@@ -5297,12 +5297,11 @@ get_base_by_token_recursive(PyTypeObject *type, void *token)
     Py_ssize_t n = PyTuple_GET_SIZE(bases);
     for (Py_ssize_t i = 0; i < n; i++) {
         PyTypeObject *base = _PyType_CAST(PyTuple_GET_ITEM(bases, i));
-        if (!_PyType_HasFeature(base, Py_TPFLAGS_HEAPTYPE)) {
-            continue;
-        }
-        if (((PyHeapTypeObject*)base)->ht_token == token) {
+        // The MRO version can slow down if this takes the same approach
+        if (PyType_GetSlot(base, Py_tp_token) == token) {
             return base;
         }
+        assert(!PyErr_Occurred());
         base = get_base_by_token_recursive(base, token);
         if (base != NULL) {
             return base;