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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 index(args):
 """ %prog index database.fasta Wrapper for `bwa index`. Same interface. """

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

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

    dbfile, = args
    check_index(dbfile)