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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 is_autosomal(chrom):
 """Keep chromosomes that are a digit 1-22, or chr prefixed digit chr1-chr22 """

    try:
        int(chrom)
        return True
    except ValueError:
        try:
            int(str(chrom.lower().replace("chr", "").replace("_", "").replace("-", "")))
            return True
        except ValueError:
            return False