Currently,
Class C(*some_classes): ...
works 'as expected' and is within grammar and language specification whereas
Class C(x for x in [object]): ...
does not work but does not cause a syntax error. I can see a use case for both in dynamic class factories. I was going to do this, but was thwarted by another issue (__doc__ cannot be assigned after creation, nor can it be defined as anything but a pure string, any work around or reason that is the case? Not true for e.g. functions).
I think having one of these within the language specification and not the other is odd.