code: def _read_23andme(file):
          
          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"
docs: 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