NEP29 (#76)

* close #77 
* adapt NEP 29
* change CI to test 3.7 - 3.10 only
* update docs with note

.github/workflows/CI.yaml

@@ -24,22 +24,14 @@ jobs:
     strategy:
       matrix:
         os: [macOS-latest, ubuntu-latest, windows-latest]
-        python-version: ["2.7", "3.5", "3.6", "3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10"]
         # Only test lowest and highest version on the expensive/slow
         # macOS and windows runners (UPDATE when supported versions change):
         exclude:
-        - os: macOS-latest
-          python-version: 3.6
-        - os: macOS-latest
-          python-version: 3.7
         - os: macOS-latest
           python-version: 3.8
         - os: macOS-latest
           python-version: 3.9
-        - os: windows-latest
-          python-version: 3.6
-        - os: windows-latest
-          python-version: 3.7
         - os: windows-latest
           python-version: 3.8
         - os: windows-latest

docs/index.rst

@@ -31,6 +31,14 @@ suite it may contain bugs. Please raise any issues or questions in the
    new data set and we will help you with the process of adding it to
    **alchemtest**.
 
+   With release 0.7.0, the alchemlyb project adopted `NEP 29`_ to determine
+   which versions of Python and NumPy_ will be supported. When we release a new
+   major or minor version, alchemtest will support *at least all minor versions
+   of Python introduced and released in the prior 42 months from the release
+   date with a minimum of 2 minor versions of Python*, and *all minor versions
+   of NumPy released in the prior 24 months from the anticipated release date
+   with a minimum of 3 minor versions of NumPy*.
+
 .. |doi| image:: https://zenodo.org/badge/83470847.svg
     :alt: Zenodo DOI
     :scale: 100%
@@ -45,7 +53,8 @@ suite it may contain bugs. Please raise any issues or questions in the
 .. _`semantic versioning`: https://semver.org   
 .. _`Issue Tracker`:
    https://github.com/alchemistry/alchemtest/issues
-
+.. _`NEP 29`: https://numpy.org/neps/nep-0029-deprecation_policy.html
+.. _NumPy: https://numpy.org
 
 .. toctree::
     :maxdepth: 1

setup.py

@@ -27,11 +27,6 @@
         'Operating System :: MacOS :: MacOS X',
         'Operating System :: Microsoft :: Windows ',
         'Programming Language :: Python',
-        'Programming Language :: Python :: 2',
-        'Programming Language :: Python :: 2.7',
-        'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
-        'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',