Hi baohua

I review all cases you commit, they are great. Since in the future, we will reuse all those cases to integrate with robot framework, So, i have a comment. we need to make sure file name is the same as class name located in that file, such as file switch_manager.txt include class SwitchManager, so i propose change switch_manager.txt to SwitchManager.txt, otherwise we will run into trouble when integrate those cases with robot.