docs: def get_repositories_by_query(self, repository_query):
          """Gets a list of ``Repositories`` matching the given repository query.
  
          arg:    repository_query (osid.repository.RepositoryQuery): the
                  repository query
          return: (osid.repository.RepositoryList) - the returned
                  ``RepositoryList``
          raise:  NullArgument - ``repository_query`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  PermissionDenied - authorization failure
          raise:  Unsupported - ``repository_query`` is not of this
                  service
          *compliance: mandatory -- This method must be implemented.*
  
          """
          # Implemented from template for
          # osid.resource.BinQuerySession.get_bins_by_query_template
          if self._catalog_session is not None:
              return self._catalog_session.get_catalogs_by_query(repository_query)
          query_terms = dict(repository_query._query_terms)
          collection = JSONClientValidated('repository',
                                           collection='Repository',
                                           runtime=self._runtime)
          result = collection.find(query_terms).sort('_id', DESCENDING)
  
          return objects.RepositoryList(result, runtime=self._runtime)