code: def labels(self, nodeids=None):
          
          if nodeids is None: nodeids = self._nodeids
          _eps = self._eps
          return [_eps[nid][2] for nid in nodeids]
docs: Return the list of labels for *nodeids*, or all labels.
  
          Args:
              nodeids: an iterable of nodeids for predications to get
                  labels from; if `None`, return labels for all
                  predications
          Note:
              This returns the label of each predication, even if it's
              shared by another predication. Thus,
              `zip(nodeids, xmrs.labels(nodeids))` will pair nodeids with
              their labels.
          Returns:
              A list of labels