Tkinter: centering windows on screen

[Kilian Lorenz]

>> that works but doesn't help me much because I'm interested in the
>> return value. So I would really like to know how to call Tk commands
>> from within Python because .... blah blah

Now I also found out how this works ... pretty easy with
<widget>.tk.call(<command>, <parameter>, <next parameter> ...)

You just have to browse Tkinter.py and get the answers to all your
questions !  :)