code: def _normalize_group_dns(self, group_dns):
          
          if isinstance(group_dns, LDAPGroupQuery):
              query = group_dns
          elif isinstance(group_dns, str):
              query = LDAPGroupQuery(group_dns)
          elif isinstance(group_dns, (list, tuple)) and len(group_dns) > 0:
              query = reduce(operator.or_, map(LDAPGroupQuery, group_dns))
          else:
              raise ValueError(group_dns)
  
          return query
docs: Converts one or more group DNs to an LDAPGroupQuery.
  
          group_dns may be a string, a non-empty list or tuple of strings, or an
          LDAPGroupQuery. The result will be an LDAPGroupQuery. A list or tuple
          will be joined with the | operator.