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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 get_chromosomes(snps):
 """ Get the chromosomes of SNPs. Parameters snps : pandas.DataFrame Returns ------- list list of str chromosomes (e.g., ['1', '2', '3', 'MT'], empty list if no chromosomes """


    if isinstance(snps, pd.DataFrame):
        return list(pd.unique(snps["chrom"]))
    else:
        return []