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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 main():
 """Main entry point for CLI commands."""

    options = docopt(__doc__, version=__version__)
    if options['segment']:
        segment(
            options['<file>'],
            options['--output'],
            options['--target-duration'],
            options['--mpegts'],
        )