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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 open_sensor( self, input_source: str, output_dest: Optional[str] = None, extra_cmd: Optional[str] = None, ) -> Coroutine: """Open FFmpeg process for read autio stream. Return a coroutine. """

        command = ["-vn", "-filter:a", "silencedetect=n={}dB:d=1".format(self._peak)]

        # run ffmpeg, read output
        return self.start_worker(
            cmd=command,
            input_source=input_source,
            output=output_dest,
            extra_cmd=extra_cmd,
            pattern="silence",
        )