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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 segment(f, output, target_duration, mpegts):
 """Segment command."""

    try:
        target_duration = int(target_duration)
    except ValueError:
        exit('Error: Invalid target duration.')

    try:
        mpegts = int(mpegts)
    except ValueError:
        exit('Error: Invalid MPEGTS value.')

    WebVTTSegmenter().segment(f, output, target_duration, mpegts)