non-iterator-returned:79:4:FirstBadIterator.__iter__:__iter__ returns non-iterator
non-iterator-returned:86:4:SecondBadIterator.__iter__:__iter__ returns non-iterator
non-iterator-returned:93:4:ThirdBadIterator.__iter__:__iter__ returns non-iterator
non-iterator-returned:100:4:FourthBadIterator.__iter__:__iter__ returns non-iterator
