They are not replicating the code at all. They are training a neural network. The neural network then learns from the code and synthesises new code.
It's no different from a human programmer reading code, learning from it, and using that experience to write new code. Somewhere in your head there is code that someone else wrote. And it's not infringing anybody's copyright for those memories to exist in your head.
It's no different from a human programmer reading code, learning from it, and using that experience to write new code. Somewhere in your head there is code that someone else wrote. And it's not infringing anybody's copyright for those memories to exist in your head.