docs: def Fierz_to_Bern_lep(C, ddll):
      """From semileptonic Fierz basis to Bern semileptonic basis for Class V.
      C should be the corresponding leptonic Fierz basis and
      `ddll` should be of the form 'sbl_enu_tau', 'dbl_munu_e' etc."""
      ind = ddll.replace('l_','').replace('nu_','')
      dic = {
          '1' + ind : 5 * C['F'+ ind + '10'] / 3 + C['F'+ ind + '9'],
          '3' + ind : -C['F' + ind + '10'] / 6,
          '5' + ind : C['F' + ind + 'S'] - 5 * C['F' + ind + 'P'] / 3,
          '7' + ind : 2 * C['F' + ind + 'P'] / 3 + C['F' + ind + 'T']
                      + C['F' + ind + 'T5'],
          '9' + ind : C['F' + ind + 'P'] / 24,
          '1p' + ind : C['F' + ind + '9p'] - 5 * C['F' + ind + '10p'] / 3,
          '3p' + ind : C['F' + ind + '10p'] / 6,
          '5p' + ind : 5 * C['F' + ind + 'Pp'] / 3 + C['F' + ind + 'Sp'],
          '7p' + ind : -2 * C['F' + ind + 'Pp'] / 3 + C['F' + ind + 'T']
                      - C['F' + ind + 'T5'],
          '9p' + ind : -C['F' + ind + 'Pp'] / 24,
      }
      return dic