invalid-format-returned:36:4:37:21:FirstBadFormat.__format__:__format__ does not return str:UNDEFINED
invalid-format-returned:43:4:44:16:SecondBadFormat.__format__:__format__ does not return str:UNDEFINED
invalid-format-returned:50:4:51:36:ThirdBadFormat.__format__:__format__ does not return str:UNDEFINED
