Tkinter, step 2: adapt imports.
diff --git a/Lib/idlelib/UndoDelegator.py b/Lib/idlelib/UndoDelegator.py
index 57b02df..d2ef638 100644
--- a/Lib/idlelib/UndoDelegator.py
+++ b/Lib/idlelib/UndoDelegator.py
@@ -1,5 +1,5 @@
 import string
-from Tkinter import *
+from tkinter import *
 
 from idlelib.Delegator import Delegator