def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def encode(self):
        return {"rx_sw_if_index": self._rx_index,
                "tx_sw_if_index": self._tx_index, "nh": self._nh_addr}