autopep8: F841 undefined name Special cases: - `long` and `unicode` no longer exist in python 3. I added a "# noqa" comment to avoid warnings. - `cmp` method no longer exist in python 3. It was used in the `test/unittest_analyze.py` file in the __cmp__ method. It appears that when this method is removed, all the tests are still valid. Therefore I dropped it.

TODO list for the rql package
=============================

* retirer les restrictions e_type = [A-Z][a-z_]*
                           r_type = [a-z_]*

* detecter les erreurs ASAP pour éviter stcheck

* tests unitaires pour sqlgen

* revoir tutoriel

* specification 1.0