Add 3.13.

.github/workflows/python-wheels.yml

@@ -22,13 +22,11 @@ jobs:
   build:
     # The type of runner that the job will run on
     runs-on: ${{ matrix.os }}
-    env:
-      PYTHON_CMD: "python${{ matrix.python-version }}"
 
     strategy:
       matrix:
         os: [ubuntu-latest, ubuntu-20.04]
-        python-version: ['3.8', '3.9', '3.10', '3.11', '3.12']
+        python-version: ['3.8', '3.9', '3.10', '3.11', '3.12', '3.13-dev']
 
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
@@ -40,6 +38,11 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
 
+      - name: Define PYTHON_CMD
+        run: |
+          PYTHON_VER="`echo ${{ matrix.python-version }} | sed 's|-dev$||'`"
+          echo "PYTHON_CMD=python${PYTHON_VER}" >> $GITHUB_ENV
+
       - name: Install dependencies
         run: |
           ${PYTHON_CMD} -m pip install --upgrade pip