Remove BaseException.with_traceback in py2 (#697)
Remove BaseException.with_traceback in py2 (#697)

This method doesn't exist in Python 2; it was added in Python 3. See https://docs.python.org/2/library/exceptions.html#exceptions.BaseException versus https://docs.python.org/3/library/exceptions.html#BaseException.with_traceback.
li-dan/typeshed,azag0/typeshed,tharvik/typeshed,euresti/typeshed,tharvik/typeshed