code: def update_connector(self, model_id, connector):
          
          model = self.get_model(model_id)
          if model is None:
              return None
          model.connector = connector
          self.replace_object(model)
          return model
docs: Update the connector information for a given model.
  
          Returns None if the specified model not exist.
  
          Parameters
          ----------
          model_id : string
              Unique model identifier
          connector : dict
              New connection information
  
          Returns
          -------
          ModelHandle