Refactoring for v3 (#133)

Author: resmo

.github/workflows/format.yml

@@ -0,0 +1,11 @@
+name: Format in Black
+on: [push, pull_request]
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: psf/black@stable
+        with:
+          options: "--check --verbose"
+          src: "."