fix python2 support

.github/workflows/regression.yml

@@ -50,3 +50,26 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: coveralls --service=github
+
+  ubuntu18_python2:
+    runs-on: ubuntu-18.04
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.4
+
+      - name: Set up Python 2.x
+        uses: actions/setup-python@v2
+        with:
+          python-version: '2.x'
+
+      - name: Prepare
+        run: lsmod && sudo apt update && sudo apt install zfsutils-linux python-setuptools && sudo -H pip install coverage unittest2 mock==3.0.5 coveralls
+
+      - name: Regression test
+        run: sudo -E ./tests/run_tests
+
+      - name: Coveralls
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: coveralls --service=github