Drop support for Python 3.9

.github/workflows/ci.yaml

@@ -81,7 +81,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.9, "3.10", "3.11", "3.12", "3.13", "3.14-dev"]
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14-dev"]
     outputs:
       python-key: ${{ steps.generate-python-key.outputs.key }}
     steps:
@@ -139,7 +139,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: [3.9, "3.10", "3.11", "3.12", "3.13", "3.14-dev"]
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14-dev"]
     steps:
       - name: Set temp directory
         run: echo "TEMP=$env:USERPROFILE\AppData\Local\Temp" >> $env:GITHUB_ENV
@@ -194,7 +194,7 @@ jobs:
       fail-fast: false
       matrix:
         # We only test on the lowest and highest supported PyPy versions
-        python-version: ["pypy3.9", "pypy3.10"]
+        python-version: ["pypy3.10"]
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@v4.2.2

.pre-commit-config.yaml

@@ -26,7 +26,7 @@ repos:
     hooks:
       - id: pyupgrade
         exclude: tests/testdata
-        args: [--py39-plus]
+        args: [--py310-plus]
   - repo: https://github.com/Pierre-Sassoulas/black-disable-checker/
     rev: v1.1.3
     hooks:

ChangeLog

@@ -32,6 +32,8 @@ Release date: TBA
 
   Closes #2513
 
+* Remove support for Python 3.9 (and constant `PY310_PLUS`).
+
 * Include subclasses of standard property classes as `property` decorators
 
   Closes #10377

astroid/__init__.py

@@ -30,9 +30,6 @@
 * builder contains the class responsible to build astroid trees
 """
 
-import functools
-import tokenize
-
 # isort: off
 # We have an isort: off on 'astroid.nodes' because of a circular import.
 from astroid.nodes import node_classes, scoped_nodes
@@ -44,7 +41,7 @@
 from astroid.bases import BaseInstance, BoundMethod, Instance, UnboundMethod
 from astroid.brain.helpers import register_module_extender
 from astroid.builder import extract_node, parse
-from astroid.const import PY310_PLUS, Context
+from astroid.const import Context
 from astroid.exceptions import (
     AstroidBuildingError,
     AstroidError,
@@ -175,12 +172,3 @@
 # isort: on
 
 from astroid.util import Uninferable
-
-# Performance hack for tokenize. See https://bugs.python.org/issue43014
-# Adapted from https://github.com/PyCQA/pycodestyle/pull/993
-if (
-    not PY310_PLUS
-    and callable(getattr(tokenize, "_compile", None))
-    and getattr(tokenize._compile, "__wrapped__", None) is None  # type: ignore[attr-defined]
-):
-    tokenize._compile = functools.lru_cache(tokenize._compile)  # type: ignore[attr-defined]