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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):
 """ Clears all members """

        # Exit the loop
        with self._lock:
            self._stop_event.set()
            self._shell_event.clear()

        if self._context is not None:
            # Unregister from events
            self._context.remove_service_listener(self)

            # Release the shell
            self.clear_shell()
            self._context = None