> But the first one is much more suggestive of a generator comprehension. I
> would want/expect it to be equivalent to itertools.chain(), not create a
> tuple.

I guess you were referring to `(*it for it in its)` (proposed notation) rather
than `(*it1, *it2, *it3)` (which already exists and builds a tuple).

Very good point!  This is confusing.  I could also read `(*it for it in its)`
as wanting to build the following generator (or something like it):