Remove unnecessary typing import. (#16777)
Summary:
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/16777
Differential Revision: D13969679
Pulled By: ezyang
fbshipit-source-id: d4728797a5927ae32628621c654eadb93c0e7682
