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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 listening and close stream"""

        if self.thread:
            self.running = False
            if isinstance(self.stream, ReadWriteStream):
                self.stream.write(b'\0' * self.chunk_size)
            self.thread.join()
            self.thread = None

        self.engine.stop()

        if self.pa:
            self.pa.terminate()
            self.stream.stop_stream()
            self.stream = self.pa = None