This NEP is a proposing a standard policy for the community to determine when we age-out support for old  versions of Python. This came out of in-person discussions at SciPy earlier in July and scattered discussion across github. This is being proposed by maintainers from Matplotlib, scikit-learn,
IPython, Jupyter, yt, SciPy, NumPy, and scikit-image.

TL;DR:

We propose only supporting versions of CPython initially released in the preceding 42 months of a major or minor release of any of our projects.

Please see https://github.com/numpy/numpy/pull/14086 and keep the discussion there as there are many interested parties (from the other projects) that may not be subscribed to the numpy mailing list.

Tom
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