code: def map_exp_ids(self, exp):
          
          names = self.exp_feature_names
          if self.discretized_feature_names is not None:
              names = self.discretized_feature_names
          return [(names[x[0]], x[1]) for x in exp]
docs: Maps ids to feature names.
  
          Args:
              exp: list of tuples [(id, weight), (id,weight)]
  
          Returns:
              list of tuples (feature_name, weight)