Drop support for Python 3.9 (EOL) (#1560)

* Drop support for Python 3.9 (EOL)

> As of 2025-10-31, 3.9 has reached the end-of-life phase of its release cycle.

https://peps.python.org/pep-0596/

* Removed some missing Python 3.9 references

Also removed an unused import, and added GitHub references to the most
recent changelog entries.

---------

Co-authored-by: Anders <6058745+ddabble@users.noreply.github.com>

Author: ulgens

.github/workflows/test.yml

@@ -11,23 +11,12 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13', '3.14']
+        python-version: ['3.10', '3.11', '3.12', '3.13', '3.14']
         django-version: ['4.2', '5.0', '5.1', '5.2', '6.0', 'main']
 
         exclude:
-          # Exclude py3.9 for Django >= 5.0,
-          # and py3.10 and py3.11 for Django > 5.2
+          # Exclude py3.10 and py3.11 for Django > 5.2
           # and py3.14 for Django < 5.2
-          - python-version: '3.9'
-            django-version: '5.0'
-          - python-version: '3.9'
-            django-version: '5.1'
-          - python-version: '3.9'
-            django-version: '5.2'
-          - python-version: '3.9'
-            django-version: '6.0'
-          - python-version: '3.9'
-            django-version: 'main'
           - python-version: '3.10'
             django-version: '6.0'
           - python-version: '3.10'

.pre-commit-config.yaml

@@ -10,7 +10,7 @@ repos:
     rev: 25.1.0
     hooks:
       - id: black
-        language_version: python3.9
+        language_version: python3.10
 
   - repo: https://github.com/codespell-project/codespell
     rev: v2.4.1
@@ -66,4 +66,4 @@ repos:
     rev: v3.20.0
     hooks:
       - id: pyupgrade
-        args: [--py39-plus]
+        args: [--py310-plus]

CHANGES.rst

@@ -4,8 +4,9 @@ Changes
 Unreleased
 ----------
 
-- Added support for Python 3.14
-- Added support for Django 6.0
+- Added support for Python 3.14 (gh-1529)
+- Added support for Django 6.0 (gh-1529)
+- Dropped support for Python 3.9 (gh-1560)
 
 3.10.1 (2025-06-20)
 -------------------

README.rst

@@ -41,7 +41,7 @@ This app supports the following combinations of Django and Python:
 ==========  ========================
   Django      Python
 ==========  ========================
-4.2         3.9, 3.10, 3.11, 3.12, 3.13
+4.2         3.10, 3.11, 3.12, 3.13
 5.0         3.10, 3.11, 3.12, 3.13
 5.1         3.10, 3.11, 3.12, 3.13
 5.2         3.10, 3.11, 3.12, 3.13, 3.14

docs/index.rst

@@ -37,7 +37,7 @@ This app supports the following combinations of Django and Python:
 ==========  =======================
   Django      Python
 ==========  =======================
-4.2         3.9, 3.10, 3.11, 3.12, 3.13
+4.2         3.10, 3.11, 3.12, 3.13
 5.0         3.10, 3.11, 3.12, 3.13
 5.1         3.10, 3.11, 3.12, 3.13
 5.2         3.10, 3.11, 3.12, 3.13, 3.14

pyproject.toml

@@ -15,7 +15,7 @@ maintainers = [
 authors = [
   { name = "Corey Bertram", email = "corey@qr7.com" },
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 classifiers = [
   "Development Status :: 5 - Production/Stable",
   "Environment :: Web Environment",
@@ -28,7 +28,6 @@ classifiers = [
   "License :: OSI Approved :: BSD License",
   "Programming Language :: Python",
   "Programming Language :: Python :: 3 :: Only",
-  "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
@@ -80,12 +79,12 @@ fragments = [
 [tool.black]
 line-length = 88
 target-version = [
-  "py39",
+  "py310",
 ]
 
 [tool.isort]
 profile = "black"
-py_version = "39"
+py_version = "310"
 
 [tool.codespell]
 skip = "AUTHORS.rst,*.po"

simple_history/template_utils.py

@@ -1,6 +1,6 @@
 import dataclasses
 from os.path import commonprefix
-from typing import Any, Final, Union
+from typing import Any, Final
 
 from django.db.models import ManyToManyField, Model
 from django.utils.html import conditional_escape
@@ -134,7 +134,7 @@ def stringify_delta_change_values(
         if all the passed elements are safe strings.
         """
 
-        def stringify_value(value: Any) -> Union[str, SafeString]:
+        def stringify_value(value: Any) -> str | SafeString:
             # If `value` is a list, stringify each element using `str()` instead of
             # `repr()` (the latter is the default when calling `list.__str__()`)
             if isinstance(value, list):

tox.ini

@@ -9,7 +9,6 @@ envlist =
 
 [gh-actions]
 python =
-    3.9: py39
     3.10: py310
     3.11: py311, docs, lint
     3.12: py312