docs: def _add_exac(self, variant_obj, info_dict):
          """Add the gmaf frequency
          
          Args:
              variant_obj (puzzle.models.Variant)
              info_dict (dict): A info dictionary
          
          """
          exac = None
          exac_keys = ['ExAC', 'EXAC', 'ExACAF', 'EXACAF']
          for key in exac_keys:
              if info_dict.get(key):
                  exac = float(info_dict[key])
          #If not found in vcf search transcripts
          if not exac:
              for transcript in variant_obj.transcripts:
                  exac_raw = transcript.ExAC_MAF
                  if exac_raw:
                      exac = float(exac_raw.split(':')[-1])
          
          if exac:
              variant_obj.add_frequency('ExAC', exac)