These classes were deprecated in Stein and marked for removal in Ussuri.
By removing these classes, we fix pep8 issues (catching-non-exception)
we started seeing at the gate with the release of astroid 2.4.0.
(cherry picked from commit 0056b5175f)
Fix E741 pep8 errors
E741 ambiguous variable name 'l'
Change 'l' to another variable in affected code.
Change-Id: Idd176e40ccf2a79832a5c99140bd30e5e1f9c0d8
(cherry picked from commit 9a1d6d3585)
0636cd1b43