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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):
 """Stops the reader an writes all remaining messages to the database. Thus, this might take a while and block. """

        BufferedReader.stop(self)
        self._stop_running_event.set()
        self._writer_thread.join()
        BaseIOHandler.stop(self)