code: def meff_hh_110(self, **kwargs):
          '''
          Returns the heavy-hole band effective mass in the [110] direction,
          meff_hh_110, in units of electron mass.
          '''
          return 2. / (2 * self.luttinger1(**kwargs) - self.luttinger2(**kwargs)
                  - 3 * self.luttinger3(**kwargs)f meff_hh_110(self, **kwargs):
          '''
          Returns the heavy-hole band effective mass in the [110] direction,
          meff_hh_110, in units of electron mass.
          '''
          return 2. / (2 * self.luttinger1(**kwargs) - self.luttinger2(**kwargs)
                  - 3 * self.luttinger3(**kwargs))
docs: Returns the heavy-hole band effective mass in the [110] direction,
          meff_hh_110, in units of electron mass.