about environment variable.

[Johan Jonkers]

What you need to do first is create a frame on which the button can be
created. Like this:

Python 1.5.2 (#6, Jun 19 2000, 15:37:01)  [GCC 2.95.2 19991024
(release)] on sunos5
Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam
>>> from Tkinter import *
>>> r=Tk()
>>> b=Button(r, text="hello world!", command="exit")
>>> b.pack()

after b.pack(), the button will appear
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