code: def clear_cache(self):
          
          self.underlying_model.clear_cache()
          try:
              logger.info('DirectView results has {} items. Clearing.'.format(
                  len(self._dv.results)
              ))
              self._dv.purge_results('all')
              if self._purge_client:
                  self._dv.client.purge_everything()
          except:
              pass
docs: Clears any cache associated with the serial model and the engines
          seen by the direct view.