created github workflow

.github/workflows/main.yml

@@ -0,0 +1,36 @@
+name: CI
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        python-version: [ '3.6', '3.7', '3.8', 'pypy3' ]
+        
+    name: Python ${{ matrix.python-version }}
+
+    steps:
+      # Checks out a copy of your repository on the machine
+      - name: Checkout code
+        uses: actions/checkout@v1
+
+      # Setup python
+      - name: Setup python
+        uses: actions/setup-python@v1
+        with:
+          python-version: ${{ matrix.python-version }}
+          architecture: x64
+        
+      # Install dependencies
+      - name: Install dependencies  
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install -r .\requirements.txt
+
+      # Run pytests
+      - name: Run pytests
+        run: |
+          pytest tests/ --showlocals --verbose