Make FakeLowP tests work (#36525)
Summary:
Make the e2e FakeLowP python tests work with Glow lowering in OSS environment. Added a README.md as a guideline.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36525
Reviewed By: hyuen
Differential Revision: D21004706
Pulled By: yinghai
fbshipit-source-id: d182152e4a1a3368640bd7872cb9ea4d4bff4b02
