[pytorch] [compososable] make contract() pickle-able through functools wraps (#92120)
Summary:
make contract() pickle-able through functools wraps.
This is to get functions wrapped with contract() to work with torch package
Differential Revision: D42491056
Pull Request resolved: https://github.com/pytorch/pytorch/pull/92120
Approved by: https://github.com/fegin, https://github.com/awgu, https://github.com/rohan-varma, https://github.com/mrshenli
