I found similar topics here of how to use the package repository from older ubuntu releases but as an beginner, I don´t know what´s the safe thing to do here:
I upgraded ubuntu from 16.10 to 17.04 without too much thinking because I did not suspect that this would brake existing software.
Now I found out that obviously there were packages removes that I need, especially "vim-nox-py2". Now i cannot find this package for zesty. How to i get back to a working system, that needs that package? How do i add the proper source from 16.10 to my sources list?