From e1ef21493f5d9c3e879d55b3a8cbf6934d0231e6 Mon Sep 17 00:00:00 2001
From: David Stansby <dstansby@gmail.com>
Date: Sat, 10 Aug 2024 09:16:40 +0100
Subject: [PATCH] Drop support for Python 3.9

---
 .github/ISSUE_TEMPLATE/bug_report.yml |  2 +-
 .github/workflows/python-package.yml  |  2 +-
 .github/workflows/releases.yml        |  2 +-
 .readthedocs.yaml                     |  2 +-
 docs/release.rst                      | 10 ++++++++--
 pyproject.toml                        |  4 ++--
 6 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/.github/ISSUE_TEMPLATE/bug_report.yml b/.github/ISSUE_TEMPLATE/bug_report.yml
index ec98af029e..7b0c4dcfc4 100644
--- a/.github/ISSUE_TEMPLATE/bug_report.yml
+++ b/.github/ISSUE_TEMPLATE/bug_report.yml
@@ -27,7 +27,7 @@ body:
     attributes:
       label: Python Version
       description: Version of Python interpreter
-      placeholder: 3.9, 3.10, 3.11, etc.
+      placeholder: 3.10, 3.11, 3.12 etc.
     validations:
       required: true
   - type: input
diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index f53cb2d9a9..61124b8e8e 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12']
+        python-version: ['3.10', '3.11', '3.12']
         numpy_version: ['>=1.24.0', '==1.23.*']
         exclude:
           - python-version: '3.10'
diff --git a/.github/workflows/releases.yml b/.github/workflows/releases.yml
index 8ac76c899b..f94711ad63 100644
--- a/.github/workflows/releases.yml
+++ b/.github/workflows/releases.yml
@@ -19,7 +19,7 @@ jobs:
       - uses: actions/setup-python@v5.1.0
         name: Install Python
         with:
-          python-version: '3.9'
+          python-version: '3.11'
 
       - name: Install PyBuild
         run: |
diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index e45cae1b45..d7190b4771 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -3,7 +3,7 @@ version: 2
 build:
   os: ubuntu-20.04
   tools:
-    python: "3.9"
+    python: "3.11"
 
 sphinx:
   configuration: docs/conf.py
diff --git a/docs/release.rst b/docs/release.rst
index 6c7ba5139b..703fec8df6 100644
--- a/docs/release.rst
+++ b/docs/release.rst
@@ -24,7 +24,13 @@ Enhancements
 ~~~~~~~~~~~~
 
 * Add Zstd codec to old V3 code path.
-  By :user:`Ryan Abernathey <rabernat>` 
+  By :user:`Ryan Abernathey <rabernat>`
+
+Maintenance
+~~~~~~~~~~~
+
+* Removed support for Python 3.9.
+  By :user:`David Stansby <dstansby>`
 
 .. _release_2.18.1:
 
@@ -51,7 +57,7 @@ Maintenance
 * Enable ruff/bugbear rules (B) and fix issues.
   By :user:`Dimitri Papadopoulos Orfanos <DimitriPapadopoulos>` :issue:`1702`.
 
-* Minor updates to use `np.inf` instead of `np.PINF` / `np.NINF` in preparation for NumPy 2.0.0 release. 
+* Minor updates to use `np.inf` instead of `np.PINF` / `np.NINF` in preparation for NumPy 2.0.0 release.
   By :user:`Joe Hamman <jhamman>` :issue:`1842`.
 
 Deprecations
diff --git a/pyproject.toml b/pyproject.toml
index dacd45ec2c..a0525a8d8a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,7 +10,7 @@ readme = { file = "README.md", content-type = "text/markdown" }
 maintainers = [
     { name = "Alistair Miles", email = "alimanfoo@googlemail.com" }
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 dependencies = [
     'asciitree',
     'numpy>=1.23',
@@ -30,9 +30,9 @@ classifiers = [
     'Topic :: Software Development :: Libraries :: Python Modules',
     'Operating System :: Unix',
     'Programming Language :: Python :: 3',
-    'Programming Language :: Python :: 3.9',
     'Programming Language :: Python :: 3.10',
     'Programming Language :: Python :: 3.11',
+    'Programming Language :: Python :: 3.12',
 ]
 license = { text = "MIT" }