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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 ffmpeg_has_loudnorm():
 """ Run feature detection on ffmpeg, returns True if ffmpeg supports the loudnorm filter """

    cmd_runner = CommandRunner([get_ffmpeg_exe(), '-filters'])
    cmd_runner.run_command()
    output = cmd_runner.get_output()
    if 'loudnorm' in output:
        return True
    else:
        logger.warning(
            "Your ffmpeg version does not support the 'loudnorm' filter. "
            "Please make sure you are running ffmpeg v3.1 or above."
        )
        return False