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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 summary(args):
 """ %prog summary cdhit.clstr Parse cdhit.clstr file to get distribution of cluster sizes. """

    from jcvi.graphics.histogram import loghistogram

    p = OptionParser(summary.__doc__)
    opts, args = p.parse_args(args)

    if len(args) != 1:
        sys.exit(not p.print_help())

    clstrfile, = args
    cf = ClstrFile(clstrfile)
    data = list(cf.iter_sizes())
    loghistogram(data, summary=True)