Add GH pipeline

.github/workflows/pipeline.yml

@@ -0,0 +1,34 @@
+name: Lint and unit tests
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  lint:
+    name: Lint (Python ${{ matrix.python-version }})
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ['3.10', '3.12']
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+          cache: 'pip'
+
+      - name: Install dependencies
+        run: pip install --quiet tox
+
+      - name: Run linting
+        run: |
+          tox -e pep8
+          tox -e mypy
+          tox -e flake8

mypy.ini

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+[mypy]
+python_version = 3.10
+strict = False
+disable_error_code = import-untyped,import-not-found
+# TODO: consider enabling the following once
+# all optional values are explicitly specified.
+no_implicit_optional = False