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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 bed(args):
 """ %prog bed maffiles > out.bed Convert a folder of maf alignments to the bed features then useful to check coverage, etc. """

    p = OptionParser(bed.__doc__)

    opts, args = p.parse_args(args)

    if len(args) != 1:
        sys.exit(p.print_help())

    flist = args
    prefix = flist[0].split(".")[0]

    j = 0
    for f in flist:
        reader = Maf(f).reader
        for rec in reader:
            a, b = rec.components

            for a, tag in zip((a, b), "ab"):
                name = "{0}_{1:07d}{2}".format(prefix, j, tag)
                print("\t".join(str(x) for x in (a.src, a.forward_strand_start, \
                        a.forward_strand_end, name)))

            j += 1