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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 start(self):
 """Start listening from stream"""

        if self.stream is None:
            from pyaudio import PyAudio, paInt16
            self.pa = PyAudio()
            self.stream = self.pa.open(
                16000, 1, paInt16, True, frames_per_buffer=self.chunk_size
            )

        self._wrap_stream_read(self.stream)

        self.engine.start()
        self.running = True
        self.is_paused = False
        self.thread = Thread(target=self._handle_predictions)
        self.thread.daemon = True
        self.thread.start()