Python's comprehensions were lifted from Haskell, and its map and filter functions also operate on iterables. They can't be purely functional because of the surrounding language, but they do follow a functional style.
(expr for item in iterable if cond) is more or less another way to spell map(lambda item: expr, filter(lambda item: cond, iterable)), except readable.
You could define "functional programming" to absolutely require referential transparency, but that's not what the rest of the thread is doing.
