deploy to pypi (#137)

.github/workflows/deploy.yml

@@ -0,0 +1,55 @@
+name: Build and upload
+
+# Build on every branch push, tag push, and pull request change:
+# on: [push, pull_request]
+# Alternatively, to publish when a (published) GitHub Release is created, use the following:
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+  release:
+    types:
+      - published
+
+jobs:
+  build_sdist:
+    name: Build Python source distribution
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          depth: 0
+
+      - uses: actions/setup-python@v2
+        name: Install Python
+        with:
+          python-version: '3.7'
+
+      - name: Build sdist
+        run: python setup.py sdist
+
+      - uses: actions/upload-artifact@v2
+        with:
+          path: dist/*.tar.gz
+
+  upload_pypi:
+    needs: [build_sdist]
+    runs-on: ubuntu-latest
+    # upload to PyPI on every tag starting with 'v'
+    # if: github.event_name == 'push' && startsWith(github.event.ref, 'refs/tags/v')
+    # alternatively, to publish when a GitHub Release is created, use the following rule:
+    if: github.event_name == 'release' && github.event.action == 'published'
+    steps:
+      - uses: actions/download-artifact@v2
+        with:
+          name: artifact
+          path: dist
+
+      - uses: pypa/gh-action-pypi-publish@master
+        with:
+          user: __token__
+          password: ${{ secrets.pypi_token }}
+          # To test: repository_url: https://test.pypi.org/legacy/