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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_23andme(file):
 """ Read and parse 23andMe file. https://www.23andme.com Parameters file : str path to file Returns ------- pandas.DataFrame individual's genetic data normalized for use with `lineage` str name of data source """

        df = pd.read_csv(
            file,
            comment="#",
            sep="\t",
            na_values="--",
            names=["rsid", "chrom", "pos", "genotype"],
            index_col=0,
            dtype={"chrom": object},
        )

        return sort_snps(df), "23andMe"