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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 cut_video_stream(stream, start, end, fmt):
 """ cut video stream from `start` to `end` time Parameters stream : bytes video file content start : float start time end : float end time Returns ------- result : bytes content of cut video """

    with TemporaryDirectory() as tmp:
        in_file = Path(tmp) / f"in{fmt}"
        out_file = Path(tmp) / f"out{fmt}"

        in_file.write_bytes(stream)

        try:
            ret = subprocess.run(
                [
                    "ffmpeg",
                    "-ss",
                    f"{start}",
                    "-i",
                    f"{in_file}",
                    "-to",
                    f"{end}",
                    "-c",
                    "copy",
                    f"{out_file}",
                ],
                capture_output=True,
            )
        except FileNotFoundError:
            result = stream
        else:
            if ret.returncode:
                result = stream
            else:
                result = out_file.read_bytes()

    return result