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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 refallele(args):
 """ %prog refallele vcffile > out.refAllele Make refAllele file which can be used to convert PLINK file to VCF file. """

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

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

    vcffile, = args
    fp = open(vcffile)
    for row in fp:
        if row[0] == '#':
            continue
        atoms = row.split()
        marker = "{0}:{1}".format(*atoms[:2])
        ref = atoms[3]
        print("\t".join((marker, ref)))