[python-win32] Default button change notification

[Howard Lightstone]

I have some buttons on a Canvas that act properly when Tab is used (a 
dim gray highlight 'ring" shows on the button).

Is there some way to change the color of the ring (or any other color 
change) when the button is the "default" button?  Focus events don't do 
the right thing.  I saw a request for a <Traverse-IN> event on a Tk list but 
that was too recent to actually be implemented on the 8.3 version I have 
available.  I can't seem to find anything to hook onto when the "default" 
button (which takes action on the spacebar) changes.

Thanks