Remove unused imports in aten/src/ATen/function_wrapper.py (#37245)
Summary:
typing is available since Python 3.5, no need to try-import.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/37245
Differential Revision: D21236650
Pulled By: albanD
fbshipit-source-id: daf150103835d0c6cd3c39300044e548bb6d311d
