I am trying to get the Python package torch-geometric to work using Nix (I am on NixOS). Currently, I use mach-nix to try and setup a Python environment. However, the difficulty is that some of the dependencies should be downloaded from a separate file server (not pypi), i.e. https://pytorch-geometric.com/whl/torch-1.8.0+cpu.html. I am first trying to setup an environment containing a single