Index: Lib/lib-tk/tkSimpleDialog.py
===================================================================
--- Lib/lib-tk/tkSimpleDialog.py	(revision 52717)
+++ Lib/lib-tk/tkSimpleDialog.py	(working copy)
@@ -124,10 +124,11 @@
         self.withdraw()
         self.update_idletasks()
 
-        self.apply()
+        try:
+            self.apply()
+        finally:
+            self.cancel()
 
-        self.cancel()
-
     def cancel(self, event=None):
 
         # put focus back to the parent window