Remove PythonPrint's is_method_ member (#25226)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25226
Given the current structure, it is easier to just call different functions
to get the desired behavior.
Test Plan: Imported from OSS
Differential Revision: D17066672
Pulled By: zdevito
fbshipit-source-id: 88e76c5ee870d9d1e9887aebcac5e7873fabe6b1
