Behavior of statistics.mean

[cametan]

This means, since Python 3.11, some "change" in Python causes its strange behavior.

Could this be the cause of the new behavior?

The statistics functions mean(), variance() and stdev() now consume iterators in one pass rather than converting them to a list first. This is twice as fast and can save substantial memory. (Contributed by Raymond Hettinger in gh-90415.)

See What's new in Python 3.11

Thanks. That could be the cause.
This seems a sort of pitfall. It might be safe to convert from the result of unfoldr to a list.

def baz():
    from statistics import mean
    def foo(x):
        i = int(input())
        return None if i == 0 else (i, x + 1)
    print(mean(list(unfoldr(foo, 0)))) # converting from unfold's iterable to list first, before passing it to statistics.mean

Anyway, thanks for your advice!