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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def handler(self):
 """Handler on explicitly closing the GUI window."""

    self.pauseMovie()
    if tkMessageBox.askokcancel("Quit?", "Are you sure you want to quit?"):
      self.exitClient()
    else: # When the user presses cancel, resume playing.
      #self.playMovie()
      print "Playing Movie"
      threading.Thread(target=self.listenRtp).start()
      #self.playEvent = threading.Event()
      #self.playEvent.clear()
      self.sendRtspRequest(self.PLAY)