Odd traceback error when a variable is not defined

[gonzalalGFM]

Morning!
We're using the rescue people example and my students are encoutering a kind of odd behaviour in the tracebacks. For instace, if at some point in the code you are using a variable that is not already assigned, instead of launching the common error in python:
line X: Undefined variable 'var' (undefined-variable)
It throughs this kind of error:
line 7: Module 'cv2' has no 'CascadeClassifier' member (no-member)
line 52: Module 'cv2' has no 'cvtColor' member (no-member)
line 52: Module 'cv2' has no 'COLOR_BGR2GRAY' member (no-member)
line 58: Module 'cv2' has no 'rectangle' member (no-member)
Leading to check the import of the libraries when the actual error is not indicated.

[javizqh]

We are aware of this problem, but we have not been able to solve it because the traceback is being generated by Ros. The only solution currently is to read properly the error traceback and find the real error