code: def _is_in_targets(self, site, targets):
          
          elems = self._get_elements(site)
          for elem in elems:
              if elem not in targets:
                  return False
          return True
docs: Test whether a site contains elements in the target list
  
          Args:
              site (Site): Site to assess
              targets ([Element]) List of elements
          Returns:
               (boolean) Whether this site contains a certain list of elements