code: def summed_icohp(self):
          
          if self._is_spin_polarized:
              sum_icohp = self._icohp[Spin.down] + self._icohp[Spin.up]
          else:
              sum_icohp = self._icohp[Spin.up]
          return sum_icohp
docs: Adds ICOHPs of both spin channels for spin polarized compounds
          Returns:
               icohp value in eV