def clear_cache(self):
        """
        Clears any cache associated with the serial model and the engines
        seen by the direct view.
        """
        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
Clears any cache associated with the serial model and the engines
        seen by the direct view.