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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 fixpairs(args):
 """ %prog fixpairs pairsfile sep sd Fix pairs library stats. This is sometime useful to modify library stats, for example, the separation between paired reads after importing the data. """

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

    if len(args) != 3:
        sys.exit(not p.print_help())

    pairsfile, sep, sd = args
    newpairsfile = pairsfile.rsplit(".", 1)[0] + ".new.pairs"
    sep = int(sep)
    sd = int(sd)

    p = PairsFile(pairsfile)
    p.fixLibraryStats(sep, sd)
    p.write(newpairsfile)