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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 read_pgroups(in_file):
 """Read HLAs and the pgroups they fall in. """

    out = {}
    with open(in_file) as in_handle:
        for line in (l for l in in_handle if not l.startswith("#")):
            locus, alleles, group = line.strip().split(";")
            for allele in alleles.split("/"):
                out["HLA-%s%s" % (locus, allele)] = group
    return out