Tkinter rename, step 2: fix imports and add stub modules.
diff --git a/Lib/lib-tk/Canvas.py b/Lib/lib-tk/Canvas.py
index 34464ab..d35b1f5 100644
--- a/Lib/lib-tk/Canvas.py
+++ b/Lib/lib-tk/Canvas.py
@@ -7,7 +7,7 @@
 warnpy3k("the Canvas module has been removed in Python 3.0", stacklevel=2)
 del warnpy3k
 
-from Tkinter import Canvas, _cnfmerge, _flatten
+from tkinter import Canvas, _cnfmerge, _flatten
 
 
 class CanvasItem: