[docs] [issue11468] Improve unittest basic example in the doc

Éric Araujo <merwok@netwok.org> added the comment: I think there’s value in accepting the current patch as really basic example, and then see if the section about setting up and tearing down also has a very simple example. ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue11468> _______________________________________