Supporting Python 3.13 (#1996)

.github/workflows/unittests.yaml

@@ -21,14 +21,15 @@ jobs:
     runs-on: ubuntu-24.04
     strategy:
       matrix:
-        python: [3.9, '3.10', '3.11', '3.12']
+        python: [3.9, '3.10', '3.11', '3.12', '3.13']
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Setup Python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python }}
+          allow-prereleases: true
       - name: Update package index
         run: sudo apt-get update
       - name: Install mpi libs

armi/utils/flags.py

@@ -91,6 +91,7 @@ def __new__(cls, name, bases, attrs):
 
         # Auto fields have been resolved, so now collect all ints
         allFields = {name: val for name, val in attrs.items() if isinstance(val, int)}
+        allFields = {n: v for n, v in allFields.items() if not _FlagMeta.isdunder(n)}
         flagClass._nameToValue = allFields
         flagClass._valuesTaken = set(val for _, val in allFields.items())
         flagClass._autoAt = autoAt
@@ -104,6 +105,10 @@ def __new__(cls, name, bases, attrs):
 
         return flagClass
 
+    @staticmethod
+    def isdunder(s):
+        return s.startswith("__") and s.endswith("__")
+
     def __getitem__(cls, key):
         """
         Implement indexing at the class level.

pyproject.toml

@@ -61,6 +61,7 @@ classifiers = [
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
     "Topic :: Scientific/Engineering :: Information Analysis",
 ]