def from_backend(self, dagobah_id):
        """ Reconstruct this Dagobah instance from the backend. """
        logger.debug('Reconstructing Dagobah instance from backend with ID {0}'.format(dagobah_id))
        rec = self.backend.get_dagobah_json(dagobah_id)
        if not rec:
            raise DagobahError('dagobah with id %s does not exist '
                               'in backend' % dagobah_id)
        self._construct_from_json(rec)
Reconstruct this Dagobah instance from the backend.