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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 blast(args):
 """ %prog blast btabfile Convert to BLAST -m8 format. """

    p = OptionParser(blast.__doc__)

    opts, args = p.parse_args(args)

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

    btabfile, = args
    btab = Btab(btabfile)
    for b in btab:
        print(b.blastline)