code: def multiplicity(self):
          
          sga = SpacegroupAnalyzer(self.bulk_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(self.bulk_structure[defindex])
          return len(equivalent_sites)
docs: Returns the multiplicity of a defect site within the structure (needed for concentration analysis)