Adhere to the standard for dropping Python versions

[datapythonista]

Maintainers from several scientific Python projects are defining a standard to for all projects to drop support of old Python versions in a synchronized way. The standard is defined in this PR: numpy/numpy#14086

I think pandas is already quite synchronized with the rest of the ecosystem, and I think the timeline of the standard matches what we have in mind in the short term (stopping support of Python 3.5 in the next release).

I create this issue to have a discussion in case anyone has comments. And I propose that if there is agreement, we adhere to the standard formally.

[TomAugspurger]

+1 to adopting it.

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On Jul 24, 2019, at 04:16, Marc Garcia ***@***.***> wrote: Maintainers from several scientific Python projects are defining a standard to for all projects to drop support of old Python versions in a synchronized way. The standard is defined in this PR: numpy/numpy#14086 I think pandas is already quite synchronized with the rest of the ecosystem, and I think the timeline of the standard matches what we have in mind in the short term (stopping support of Python 3.5 in the next release). I create this issue to have a discussion in case anyone has comments. And I propose that if there is agreement, we adhere to the standard formally. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[jorisvandenbossche]

+1 as well

[jbrockmendel]

Works for me.

[simonjayhawkins]

from https://numpy.org/neps/nep-0029-deprecation_policy.html#implementation

Implementation
We suggest that all projects adopt the following language into their development guidelines:

This project supports:

All minor versions of Python released 42 months prior to the project, and at minimum the two latest minor versions.

All minor versions of numpy released in the 24 months prior to the project, and at minimum the last thee minor versions.

In setup.py, the python_requires variable should be set to the minimum supported version of Python. All supported minor versions of Python should be in the test matrix and have binary artifacts built for the release.

Minimum Python and NumPy version support should be adjusted upward on every major and minor release, but never on a patch release.

[mroeschke]

Think all that's left is documenting that we mirror numpy in https://pandas.pydata.org/docs/development/policies.html

[Sadin]

Hello all, I'd like to tackle this, what needs to be updated? Docs?

[MarcoGorelli]

That's right