diff --git a/Lib/lib-tk/test/test_ttk/test_extensions.py b/Lib/lib-tk/test/test_ttk/test_extensions.py
index 110249d..56d32e5 100644
--- a/Lib/lib-tk/test/test_ttk/test_extensions.py
+++ b/Lib/lib-tk/test/test_ttk/test_extensions.py
@@ -45,7 +45,7 @@
         # it tries calling instance attributes not yet defined.
         ttk.LabeledScale(variable=myvar)
         if hasattr(sys, 'last_type'):
-            self.assertNotEqual(sys.last_type, tkinter.TclError)
+            self.assertNotEqual(sys.last_type, Tkinter.TclError)
 
 
     def test_initialization(self):