def save(self):
        tmp_path = self.path + '.tmp'
        with open(tmp_path, 'w') as f:
            f.write(json.dumps(self.body_labels.items()))
        os.rename(tmp_path, self.path)
def __init__(self, test, rx_index, tx_index, nh_addr):
        self._test = test
        self._rx_index = rx_index
        self._tx_index = tx_index
        self._nh_addr = ip_address(nh_addr)