Drop some Python 2 compatibility code (#51769)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/51769
Remove some Python 2 compatibility code that otherwise causes errors to
be reported from static type checkers.
Static type checkers complain that the old Python 2 modules and
functions referenced by this code do not exist. Given that Python 2
support is entirely deprecated now we can simply remove the
compatibility code.
ghstack-source-id: 121313191
Test Plan:
Was able to get Pyre to successfully type check the `caffe2/python`
directory with this and some other changes.
Reviewed By: Tianshu-Bao
Differential Revision: D26271723
Pulled By: simpkins
fbshipit-source-id: fec8a09466be6867388832380480aafd36616aa1
