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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 exitClient(self):
 """Teardown button handler."""

    self.sendRtspRequest(self.TEARDOWN)
    #self.handler()
    os.remove(CACHE_FILE_NAME + str(self.sessionId) + CACHE_FILE_EXT) # Delete the cache image from video
    rate = float(self.counter/self.frameNbr)
    print('-'*60 + "\nRTP Packet Loss Rate :" + str(rate) +"\n" + '-'*60)
    sys.exit(0)