[FX] Added invert example (#51478)
Summary:
Added an inverse example.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/51478
Reviewed By: pbelevich
Differential Revision: D26190544
Pulled By: Chillee
fbshipit-source-id: 4324ea8b917557f4c49f3b9aecd35c4e9ab36bf3
