add workflow

.github/workflows/release.yaml

@@ -0,0 +1,25 @@
+name: "Publish to PyPI"
+on:
+  release:
+    types:
+      - published
+jobs:
+  build-n-publish:
+    name: Build and publish
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@master
+      - uses: actions/setup-python@v2
+        with:
+          python-version: '3.7'
+          architecture: 'x64'
+      - name: Run build script
+        run: |
+          pip install twine --user
+          pip install wheel
+          BM_BUILD=1 BM_VERSION=${GITHUB_REF##refs/tags/v} python3 setup.py sdist --format=gztar  
+      - name: Publish distribution 📦 to PyPI
+        uses: pypa/gh-action-pypi-publish@master
+        with:
+            user: __token__
+            password: ${{ secrets.pypi_password }}