updated workflow

.github/workflows/pythonpublish.yml

@@ -12,12 +12,12 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v1
       with:
-        python-version: '3.8'
+        python-version: '3.x'
     - name: Install dependencies
       run: |
         cd python
         python -m pip install --upgrade pip
-        pip install setuptools wheel twine
+        pip install setuptools wheel
         pip install -r requirements.txt
     - name: Build and publish
       env:
@@ -26,4 +26,5 @@ jobs:
       run: |
         cd python
         python setup.py sdist bdist_wheel
+        pip install twine
         twine upload dist/*