Remove Incorrect Comment in tools/build_libtorch and remove Python2 support in the module import (#44888)
Summary:
Fixes #{44293} and removes Python2 imports from MNIST download module as Python2 is not being supported.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/44888
Reviewed By: agolynski
Differential Revision: D23785579
Pulled By: bugra
fbshipit-source-id: d9380502380876282008dd2d5feb92a446648982
