Section A.9 says that the issue with Exception objects that are not iterable and indexable is supported by 2to3.
But it seems that it doesn't. I tried the code presented as the example:
e = Exception('arg1', 'arg2')
e[1]
and found that it is not converted by 2to3. This fix is not mentioned neither in documentation, nor in the code of fix_except fixer.
Maybe am I missing something?