code: def apply_operation(self, symmop):
          
  
          def operate_site(site):
              new_cart = symmop.operate(site.coords)
              return Site(site.species, new_cart,
                          properties=site.properties)
  
          self._sites = [operate_site(s) for s in self._sites]
docs: Apply a symmetry operation to the molecule.
  
          Args:
              symmop (SymmOp): Symmetry operation to apply.