diff --git a/src/test_typing_extensions.py b/src/test_typing_extensions.py
index 208382a0..ad32e0e2 100644
--- a/src/test_typing_extensions.py
+++ b/src/test_typing_extensions.py
@@ -1859,8 +1859,8 @@ def __init__(self):
         class DI:
             def __init__(self):
                 self.x = None
-        self.assertIsInstance(C(), P)
-        self.assertIsInstance(D(), P)
+        self.assertIsInstance(CI(), P)
+        self.assertIsInstance(DI(), P)
 
     def test_protocols_in_unions(self):
         class P(Protocol):