code: def get_gold_labels(self, cand_lists, annotator=None):
          
          return get_sparse_matrix(self.session, GoldLabelKey, cand_lists, key=annotator)
docs: Load sparse matrix of GoldLabels for each candidate_class.
  
          :param cand_lists: The candidates to get gold labels for.
          :type cand_lists: List of list of candidates.
          :param annotator: A specific annotator key to get labels for. Default
              None.
          :type annotator: str
          :return: A list of MxN sparse matrix where M are the candidates and N is the
              annotators. If annotator is provided, return a list of Mx1 matrix.
          :rtype: list[csr_matrix]