Two independent windows,but part of same process
import sys
from Tkinter import Toplevel, Button, Label
win1 = Toplevel()
win2 = Toplevel()
Button(win1, text='Button 1', command=sys.exit).pack()
Button(win2, text='Button 2', command=sys.exit).pack()
Label(text='Popups').pack()
win1.mainloop()
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