[FX] Update docstring code/graph printout (#50396)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/50396
Test Plan: Imported from OSS
Reviewed By: Chillee
Differential Revision: D25874253
Pulled By: jamesr66a
fbshipit-source-id: 6217eadbcbe823db14df25070eef411e184c2273
