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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 gff(args):
 """ %prog gff seq.gbk Convert Genbank file to GFF and FASTA file. The Genbank file can contain multiple records. """

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

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

    gbkfile, = args
    MultiGenBank(gbkfile)