def _to_dict(self):
        """Return a json dictionary representing this model."""
        _dict = {}
        if hasattr(self, 'entities') and self.entities is not None:
            _dict['entities'] = [x._to_dict() for x in self.entities]
        if hasattr(self, 'pagination') and self.pagination is not None:
            _dict['pagination'] = self.pagination._to_dict()
        return _dict
Return a json dictionary representing this model.