My linter says `feed` is undefined for this line: https://github.com/wking/rss2email/blob/master/rss2email/feed.py#L439 [This line above](https://github.com/wking/rss2email/blob/master/rss2email/feed.py#L377) uses `self` instead of `feed`, so the linter´s warning makes sense to me, but didn't test the code.