Fix C412 lint from flake8-comprehensions update. (#24184)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/24184
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D16764168
Pulled By: ezyang
fbshipit-source-id: cc252a860fd7e4b7fb2b95c5d9fcdbf6935ffeb6
