how do I quit exec Tkinter scripts???

[revyakin]

Sorry, this may sound extremely dumb, but I just started playing
around with Tkinter (python 2.2) on win 98, and I seem to be unable to
quit tkinter scripts. E.g. the following hello world script is copied
and pasted from pythonware.com... I run it from python shell and when
I close the window that pops up the program keeps running and nothing
brings the prompt again. Same thing happens when running from C: The
site says it should quit by closing the GUI window... but it never
does. Huh???

# File: bind1.py

from Tkinter import *

root = Tk()

def callback(event):
    print "clicked at", event.x, event.y 

frame = Frame(root, width=100, height=100)
frame.bind("<Button-1>", callback)
frame.pack()

root.mainloop()