I want to write a python code for automated action,

In my task, there are certain stages 

See the above image,

There is a radio field called Ready for Implementation? 

if the user clicks Yes, if should automatically change the stage to READY FOR IMPLEMENTATION, 

If they clicks No, I have remarks, It should automatically change the stage to Remarks before Implementation

For this purpose I have given an automated action

But I am not sure the python code is correct