You don’t need to change your current setup, if you create a new virtual environment.
I’m personally using conda, as I think their env setup is convenient to switch quickly and in the worst case, you can just delete a “broken” environment.

download Anaconda
create a new env via: conda create -n my_env_name Python=3.7 Anaconda (the last Anaconda argument pulls in a lot of libs like numpy, matplitlib etc., so you might want to skip it)
activate the env via: conda activate my_env_name

install the PyTorch binaries