[DO NOT MERGE] check that test case is working as expected

cf. #9348 cc @jab

Author: JelleZijlstra

test_cases/stdlib/typing/check_regression_issue_9296.py

@@ -13,4 +13,4 @@ class MyKeysView(t.KeysView[KT]):
 dict_keys = type(d.keys())
 
 # This should not cause an error like `Member "register" is unknown`:
-MyKeysView.register(dict_keys)
+MyKeysView.regixster(dict_keys)