Not installed correctly when install from setup.py scripts

Hi,

I'm trying to run the GraphCast package which depends on this package. If I build this package from source and manually copy the files into my GraphCast venv I can run the package.

It seems this is a problem with this setup, as I can never actually install this using a `setup.py` script.

I've built a minimal reproduction that fails. I can see that you have some setup for building M1 arm binaries so I think this *should* work?

My reproduction can be found here: https://github.com/JoachimKoenigslieb/dm-tree-build-error/tree/main.

My environment is an M1 MacBook pro 32 GB running Sonoma 14.3.1 with Python 3.11.6.

If there is anything else I can do, let me know!