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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 stop(self):
 """ Stop notifier's loop. Stop notification. Join the thread. """

        self._stop_event.set()
        os.write(self._pipe[1], b'stop')
        threading.Thread.join(self)
        Notifier.stop(self)
        self._pollobj.unregister(self._pipe[0])
        os.close(self._pipe[0])
        os.close(self._pipe[1])