Rebuild for python39

[regro-cf-autotick-bot]

This PR has been triggered in an effort to update python39.

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[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[github-actions]

Hi! This is the friendly conda-forge automerge bot!

I considered the following status checks when analyzing this PR:

• linter: passed
• drone: passed
• travis: passed
• azure: passed

Thus the PR was passing and merged! Have a great day!

[beckermr]

Should this have passed @rgommers?

[rgommers]

Yes, I believe SciPy 1.5.2 is compatible with Python 3.9. We haven't uploaded wheels to PyPI, rather will do that with 1.5.3 which is imminent - but I don't think it contains any essential bug fixes.

[h-vetinari]

@conda-forge/core - how can we get windows builds for scipy on 3.9? Bascially all recipes depending on scipy will (currently) fail on windows during the 3.9-migration.

[ocefpaf]

We can try to make special builds with mkl but usually we rely on AnacondaInc to do those. Sadly we never nailed our own build with openblas.

[h-vetinari]

I'm aware of that, but I was asking not least in the context of @mariusvniekerk manually building for 3.8, see #119.

For proper cf-based infra, I believe the current plan (cf #80) is to wait for LLVM to be able to compile fortran with flang, but the just-released 11.0 does not generate IR yet.

[ocefpaf]

Yeah. I was avoiding asking people to do extra work unless they volunteer for it themselves :-)

We do have a Windows machine from ovh now that may make this a bit easier. Stay tuned.