Wrong helper function imported in SE(3) exercises

[amoreau96]

In SE(3) exercises, the imported helper_func.py is from the transformation_2d lessons.

I assume this is because the students might want to use some of its functions for the first exercise. Won't it crash when you try to run the exercises from the student's zip file, since the 2D helper_func.py isn't included in the zip file?

Apologies in advance if this is the desired behavior.

[pomerlef]

Thanks, we will investigate that. It could be from a wrong copy-paste.

I would add that, having multiple files named helper_func.py is not the best for maintenance. We should be more explicit for these file names.