CI: use macos-26

the Github runner is out of beta

.github/workflows/modified_scripts_build.yml

@@ -83,7 +83,11 @@ jobs:
       fail-fast: false
       matrix:
         python-version: ${{fromJson(needs.discover_modified_scripts.outputs.versions)}}
-        os: ["macos-14", "macos-15", "macos-15-intel"]
+        os:
+          - macos-14
+          - macos-15
+          - macos-15-intel
+          - macos-26
         exclude: ${{fromJson(needs.discover_modified_scripts.outputs.versions_macos_build_exclude)}}
     runs-on: ${{ matrix.os }}
     steps:
@@ -193,7 +197,9 @@ jobs:
       fail-fast: false
       matrix:
         python-version: ${{fromJson(needs.discover_modified_scripts.outputs.versions)}}
-        os: ["ubuntu-22.04", "ubuntu-24.04"]
+        os:
+          - ubuntu-22.04
+          - ubuntu-24.04
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v6

.github/workflows/pyenv_tests.yml

@@ -10,11 +10,12 @@ jobs:
       fail-fast: false
       matrix:
         os:
-          - ubuntu-24.04
           - ubuntu-22.04
-          - macos-15-intel
-          - macos-15
+          - ubuntu-24.04
           - macos-14
+          - macos-15
+          - macos-15-intel
+          - macos-26
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v6

plugins/python-build/scripts/add_cpython.py

@@ -32,9 +32,8 @@ import tqdm
 
 logger = logging.getLogger(__name__)
 
-CUTOFF_VERSION=packaging.version.Version('3.9')
+CUTOFF_VERSION=packaging.version.Version('3.10')
 EXCLUDED_VERSIONS= {
-    packaging.version.Version("3.9.3")  #recalled upstream
 }
 
 here = pathlib.Path(__file__).resolve()
@@ -168,7 +167,6 @@ def handle_t_thunks(version, previous_version, is_prerelease_upgrade):
     thunk_name = (str(version) + "t")
     thunk_path = OUT_DIR / thunk_name
     previous_thunk_name = str(previous_version) + "t"
-    previous_thunk_path = OUT_DIR / previous_thunk_name
     if is_prerelease_upgrade:
         logger.info(f"Git moving {previous_thunk_name} to {thunk_name}")
         subprocess.check_call(("git","-C",OUT_DIR,