Button width
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from Tkinter import *
root = Tk()
def callback():
print "called the callback!"
# create a toolbar
toolbar = Frame(root)
b = Button(toolbar, text="new", width=16, command=callback)
b.pack(side=LEFT, padx=2, pady=2)
b = Button(toolbar, text="open", width=6, command=callback)
b.pack(side=LEFT, padx=2, pady=2)
toolbar.pack(side=TOP, fill=X)
mainloop()
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