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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 fasta2bed(fastafile):
 """ Alternative BED generation from FASTA file. Used for sanity check. """

    dustfasta = fastafile.rsplit(".", 1)[0] + ".dust.fasta"
    for name, seq in parse_fasta(dustfasta):
        for islower, ss in groupby(enumerate(seq), key=lambda x: x[-1].islower()):
            if not islower:
                continue
            ss = list(ss)
            ms, mn = min(ss)
            xs, xn = max(ss)
            print("\t".join(str(x) for x in (name, ms, xs)))