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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 convert_wav(org_wav_fn: Path, tgt_wav_fn: Path) -> None: """ Converts the wav into a 16bit mono 16000Hz wav. Args: org_wav_fn: A `Path` to the original wave file tgt_wav_fn: The `Path` to output the processed wave file """

    if not org_wav_fn.exists():
        raise FileNotFoundError
    args = [config.FFMPEG_PATH,
            "-i", str(org_wav_fn), "-ac", "1", "-ar", "16000", str(tgt_wav_fn)]
    subprocess.run(args)