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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 blat(args):
 """ %prog blat old.fasta new.fasta Generate psl file using blat. """

    p = OptionParser(blat.__doc__)
    p.add_option("--minscore", default=100, type="int",
                 help="Matches minus mismatches gap penalty [default: %default]")
    p.add_option("--minid", default=98, type="int",
                 help="Minimum sequence identity [default: %default]")
    p.set_cpus()
    opts, args = p.parse_args(args)

    if len(args) != 2:
        sys.exit(not p.print_help())

    oldfasta, newfasta = args
    twobitfiles = []
    for fastafile in args:
        tbfile = faToTwoBit(fastafile)
        twobitfiles.append(tbfile)

    oldtwobit, newtwobit = twobitfiles
    cmd = "pblat -threads={0}".format(opts.cpus) if which("pblat") else "blat"
    cmd += " {0} {1}".format(oldtwobit, newfasta)
    cmd += " -tileSize=12 -minScore={0} -minIdentity={1} ".\
                format(opts.minscore, opts.minid)
    pslfile = "{0}.{1}.psl".format(*(op.basename(x).split('.')[0] \
                for x in (newfasta, oldfasta)))
    cmd += pslfile
    sh(cmd)