Tkinter rename, step 2: fix imports and add stub modules.
diff --git a/Lib/idlelib/CallTipWindow.py b/Lib/idlelib/CallTipWindow.py
index 2223885..27ed085 100644
--- a/Lib/idlelib/CallTipWindow.py
+++ b/Lib/idlelib/CallTipWindow.py
@@ -4,7 +4,7 @@
 Used by the CallTips IDLE extension.
 
 """
-from Tkinter import *
+from tkinter import *
 
 HIDE_VIRTUAL_EVENT_NAME = "<<calltipwindow-hide>>"
 HIDE_SEQUENCES = ("<Key-Escape>", "<FocusOut>")