code: def multiplicity(self):
          
          if self._multiplicity is None:
              # generate multiplicity based on space group symmetry operations performed on defect coordinates
              try:
                  d_structure = create_saturated_interstitial_structure(self)
              except ValueError:
                  logger.debug('WARNING! Multiplicity was not able to be calculated adequately '
                               'for interstitials...setting this to 1 and skipping for now...')
                  return 1
  
              sga = SpacegroupAnalyzer(d_structure)
              periodic_struc = sga.get_symmetrized_structure()
              poss_deflist = sorted(
                  periodic_struc.get_sites_in_sphere(self.site.coords, 2, include_index=True),
                  key=lambda x: x[1])
              defindex = poss_deflist[0][2]
  
              equivalent_sites = periodic_struc.find_equivalent_sites(periodic_struc[defindex])
              return len(equivalent_sites)
  
          else:
              return self._multiplicity
docs: Returns the multiplicity of a defect site within the structure (needed for concentration analysis)