add deepcopy support to subclasses (#65584)
Summary:
Happy to get any feedback on how to make this code cleaner!
This:
- Fix Tensor attribute deepcopy BC-breaking?
- Add a test for Tensor attribute deepcopy
- Fix subclass deepcopy
- Moves the subclass serialization tests into their own class not to interfere with other serialization test logic
- Add a test for subclass deepcopy
cc ezyang gchanan
Pull Request resolved: https://github.com/pytorch/pytorch/pull/65584
Reviewed By: gchanan
Differential Revision: D31206590
Pulled By: albanD
fbshipit-source-id: 74a8f0767f4933b9c941fbea880a8fd1b893ea2f
