mitogen: Re-declare Python 2.4 compatibility

With CentOS 5 now covered by the Mitogen unit tests I'm content to
reverse/clarify 104865e866

docs/changelog.rst

@@ -21,6 +21,7 @@ To avail of fixes in an unreleased version, please download a ZIP file
 In progress (unreleased)
 ------------------------
 
+* :gh:issue:`1237` :mod:`mitogen`: Re-declare Python 2.4 compatibility
 
 v0.3.35 (2025-12-01)
 --------------------

docs/index.rst

@@ -332,12 +332,16 @@ a large fleet of machines, or to alert the parent of unexpected state changes.
 Compatibility
 #############
 
-Mitogen is compatible with **Python 2.4** released November 2004, making it
+``mitogen.*`` is compatible with Python 2.4 - 2.7 and 3.6 onward; making it
 suitable for managing a fleet of potentially ancient corporate hardware, such
 as Red Hat Enterprise Linux 5, released in 2007.
 
-Every combination of Python 3.x/2.x parent and child should be possible,
+Every combination of Python 3.x/2.x parent and child should be possible.
-however at present only Python 2.4, 2.6, 2.7 and 3.6 are tested automatically.
+Automated testing cannot cover every combination, automated testing tries to
+cover the extemities (e.g. Python 3.14 parent -> Python 2.4 child).
+
+``ansible_mitogen.*`` is compatible with Python 2.7 and 3.6 onward; making it
+suitable for Ansible 2.10 onward.
 
 
 Zero Dependencies

setup.py

@@ -82,7 +82,7 @@ setup(
     license = 'BSD-3-Clause',
     url = 'https://github.com/mitogen-hq/mitogen/',
     packages = find_packages(exclude=['tests', 'examples']),
-    python_requires='>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*',
+    python_requires='>=2.4, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*',
     zip_safe = False,
     classifiers = [
         'Environment :: Console',
@@ -91,6 +91,9 @@ setup(
         'Operating System :: MacOS :: MacOS X',
         'Operating System :: POSIX',
         'Programming Language :: Python',
+        'Programming Language :: Python :: 2.4',
+        'Programming Language :: Python :: 2.5',
+        'Programming Language :: Python :: 2.6',
         'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.6',