FastAI installation dependency conflict between cymem and wheel

[rupertpople]

FastAI installation dependency conflict between cymem and wheel

[warner-benjamin]

The latest release of PyTorch doesn't support Python 3.12, so fastai currently does not support it either.

Could you provide more details about the error? I am unable to replicate it on a new Python 3.11 environment. The fastai CI tests Python 3.8-3.10 and this error crop up either.

[steve-estes]

The issue is the requirements peg to cymem==2.0.2. I get the exact same as rupert above:

ERROR: Some build dependencies for cymem==2.0.2 from https://files.pythonhosted.org/packages/8b/dc/0976e04cc46f86e0dd3ee3797ec68057eaafebf31daca9a076dc138b9920/cymem-2.0.2.tar.gz (from fastai) conflict with the backend dependencies: wheel==0.42.0 is incompatible with wheel>=0.32.0,<0.33.0.

If we want to use fastai for some of its utils, even without PyTorch (e.g. we're fans of df_shrink), this prevents us from doing so on Python 3.12. A simple fix would be to remove the version peg, instead just say cymem>=2.0.2. cymem has (as of last Sept) released a version which fixes the wheel compatibility issue, all you need to do is allow people to use it.

Also, PyTorch supports Python 3.12 in its RC from a month ago (see: pytorch/pytorch#110436 ), so we can expect a stable release that supports it shortly. So testing fastai on 3.12, including for issues like this, is probably going to be an increasing priority - e.g. Homebrew now ships 3.12 by default on Mac, etc.

[warner-benjamin]

@steve-estes fastai doesn't directly require cymem, so it must be from an upstream requirement. You can see fastai's requirements here. If you could figure out which package is pinning to cymem-2.0.2, we can raise the issue with the maintainers or look into a workaround.