code: def iter_genotypes(self):
          
          # Parsing each column of the dataframe
          for variant in self.df.columns:
              genotypes = self.df.loc[:, variant].values
              info = self.map_info.loc[variant, :]
  
              yield Genotypes(
                  Variant(info.name, info.chrom, info.pos, [info.a1, info.a2]),
                  genotypes,
                  reference=info.a2,
                  coded=info.a1,
                  multiallelic=False,
              )
docs: Iterates on available markers.
  
          Returns:
              Genotypes instances.