Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71604
Implement 2 helper functions:
- as_functional_optim which takes in a torch.optim class type and arguments and
creates the corresponding functional optimizer.
- create_functional_optim which takes in the functional optimizer class type
and constructs it. Note that as_functional_optim calls into
create_functional_optim.
The first will be used in future PRs as described in
https://github.com/pytorch/pytorch/issues/67570 to create a functional
optimizer from a traditional optimizer. The latter is used in
_OptimizerHookState to create a functional optimizer.
Both new helper functions are covered by unittests.
ghstack-source-id: 147577170
Test Plan: CI
Reviewed By: cbalioglu
Differential Revision: D33688995
fbshipit-source-id: 8b2daafd1b914efa90877cc4313aa9a428546fc1
(cherry picked from commit 42fdae2991)
