UUID4 does not rely on the machine's MAC address, from the documentation:
If all you want is a unique ID, you should probably call uuid1() or uuid4(). Note that uuid1() may compromise privacy since it creates a UUID > containing the computer’s network address. uuid4() creates a random UUID.
However, UUIDs of any kind do not promise to be cryptographically secure as it is not guaranteed in the RFC. Certain implementations may use a cryptographically secure random number generator, but I wouldn't rely on it. I would choose to use another library if that is what is needed. If you are using Python3 you can use the secrets library which has functions for doing just this.
