def METHOD_NAME(self):
    runner = CliRunner()
    db = Db()
    obj = {'config_db':db.cfgdb}
    action = 'forward'
    iface = 'Ethernet0'
    iface_alias = 'etp1'
    os.environ['SONIC_CLI_IFACE_MODE'] = "alias"
    result = runner.invoke(config.config.commands['interface'].commands["ip"].commands['loopback-action'], [iface_alias, action], obj=obj)
    os.environ['SONIC_CLI_IFACE_MODE'] = "default"
    table = db.cfgdb.get_table('INTERFACE')
    assert(table[iface]['loopback_action'] == action)
    print(result.exit_code, result.output)
    assert result.exit_code == 0