can itertools compact a list removing all of some value?

[Skaperen]

i have a huge list (approaching a billion items) which is mostly strings and/or numbers, but there are a lot of None values in there, too. i would like to compact the list in place by removing all the None values. can a method in some module do this or do i need to figure this out? the import part is to not duplicate the list since that would cause more swapping delays. but something that copies the remainder of the list each time it finds a None is also a bad idea since it bumps it up to O(n**2). something that morphs the list into a tuple is OK, since it is not modified after this.

i have looked over itertools but nothing seems obvious.