You can "launder" away the license of any source code you have copied simply by deleting it! No snazzy neural network needed.. The litigants argument is that this is what GitHub CoPilot does. It allows others to publish derivative works of copyrighted works with the license deleted. Given that it apparently is trivial to get CoPilot to spit out nearly verbatim copies of the code that it was trained on, I don't think it satisfies the "transformative" requisite of the (American) Fair use doctrine.