Update minimal Python/numpy requirements

Follows NEP29

.github/workflows/publish_to_pypi.yml

@@ -2,7 +2,21 @@ name: Build and publish to TestPyPI or PyPI
 on: [push, pull_request]
 
 jobs:
+  get_python_versions:
+    name: "Determine Python versions"
+    runs-on: ubuntu-latest
+    outputs:
+      min-python: ${{ steps.nep29.outputs.min-python }}
+      max-python: ${{ steps.nep29.outputs.max-python }}
+    steps:
+      - name: "calculate versions according to NEP29"
+        id: nep29
+        uses: mstimberg/github-calc-nep29@v0.5
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
   build:
+    needs: [get_python_versions]
     name: Build 🎡 on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:
@@ -22,7 +36,7 @@ jobs:
         with:
           output-dir: dist
         env:
-          CIBW_PROJECT_REQUIRES_PYTHON: ">=3.7"
+          CIBW_PROJECT_REQUIRES_PYTHON: ">=${{ needs.get_python_versions.outputs.min-python }}"
           CIBW_ARCHS_WINDOWS: auto64
           CIBW_ARCHS_MACOS: x86_64 universal2
           CIBW_TEST_SKIP: '*_arm64 *_universal2:arm64'
@@ -36,6 +50,7 @@ jobs:
           path: dist
 
   build-linux:
+    needs: [get_python_versions]
     name: Build ${{ matrix.arch }} 🎡 and source 📦 on Linux
     runs-on: ubuntu-latest
     strategy:
@@ -65,7 +80,7 @@ jobs:
         with:
           output-dir: dist
         env:
-          CIBW_PROJECT_REQUIRES_PYTHON: ">=3.7"
+          CIBW_PROJECT_REQUIRES_PYTHON: ">=${{ needs.get_python_versions.outputs.min-python }}"
           CIBW_ARCHS_LINUX: ${{ matrix.arch }}
           CIBW_MANYLINUX_X86_64_IMAGE: manylinux2014
           CIBW_SKIP: 'pp* *-musllinux_*'

docs_sphinx/introduction/release_notes.rst

@@ -5,7 +5,9 @@ Brian 2.5.2
 -----------
 This new minor release fixes incompatibility issues with the latest numpy release, and a number of other issues.
 To make it easier to contribute to Brian, we have now adopted a consistent code style and updated our infrastructure so
-that the style gets enforced for all new code contributions (see :ref:`code_style` for details).
+that the style gets enforced for all new code contributions (see :ref:`code_style` for details). Following
+`NEP 29 <https://numpy.org/neps/nep-0029-deprecation_policy.html>`_, this release supports Python 3.9 & numpy 1.21 and
+newer.
 
 New features
 ~~~~~~~~~~~~

pyproject.toml

@@ -9,15 +9,15 @@ requires = [
 build-backend = "setuptools.build_meta"
 
 [tool.black]
-target-version = ['py38']
+target-version = ['py39']
 include = '^/brian2/.*\.pyi?$'
 extend-exclude = '^/brian2/_version.py$'
 preview = true
 
 [tool.isort]
 atomic = true
 profile = "black"
-py_version = "38"
+py_version = "39"
 skip_gitignore = true
 # NOTE: isort has no "include" option, only "skip".
 extend_skip = ["brian2/_version.py"]

setup.py

@@ -157,7 +157,7 @@ def build_extension(self, ext):
                     'brian2.random': ['randomkit/randomkit.c',
                                       'randomkit/randomkit.h']
                     },
-      install_requires=['numpy>=1.17',
+      install_requires=['numpy>=1.21',
                         'cython>=0.29',
                         'sympy>=1.2',
                         'pyparsing',
@@ -169,6 +169,7 @@ def build_extension(self, ext):
       setup_requires=['numpy>=1.10',
                       'setuptools>=24.2'
                       ],
+      python_requires='>=3.9',
       cmdclass=versioneer.get_cmdclass({'build_ext': optional_build_ext}),
       provides=['brian2'],
       extras_require={'test': ['pytest',
@@ -199,6 +200,5 @@ def build_extension(self, ext):
           'Programming Language :: Python',
           'Programming Language :: Python :: 3',
           'Topic :: Scientific/Engineering :: Bio-Informatics'
-      ],
-      python_requires='>=3.7'
+      ]
       )