def _to_dict(self):
        """Return a json dictionary representing this model."""
        _dict = {}
        if hasattr(self, 'gateway_id') and self.gateway_id is not None:
            _dict['gateway_id'] = self.gateway_id
        if hasattr(self, 'name') and self.name is not None:
            _dict['name'] = self.name
        if hasattr(self, 'status') and self.status is not None:
            _dict['status'] = self.status
        if hasattr(self, 'token') and self.token is not None:
            _dict['token'] = self.token
        if hasattr(self, 'token_id') and self.token_id is not None:
            _dict['token_id'] = self.token_id
        return _dict
Return a json dictionary representing this model.