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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_ssm_locs(in_file):
 """Map SSMs to chromosomal locations. """

    out = {}
    with open(in_file) as in_handle:
        in_handle.readline()  # header
        for line in in_handle:
            sid, loc = line.split()[:2]
            chrom, pos = loc.split("_")
            out[sid] = (chrom, int(pos))
    return out