Merge pull request #4 from larsenv/three

Change the Python version

.github/workflows/build.yml

@@ -15,7 +15,7 @@ jobs:
     - name: Set up Python 3
       uses: actions/setup-python@v1
       with:
-        python-version: '3.x'
+        python-version: '3.7'
     - name: Install requirements with PIP
       run: pip install -r requirements.txt
     - name: Install pyinstaller