Mypy action.

.github/workflows/check_with_mypy.yml

@@ -0,0 +1,26 @@
+name: Check with mypy
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  type-check:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v2
+
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.8
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install mypy
+
+      - name: Run mypy
+        run: mypy py3xui