Enable python3.5

Author: Yibo-Chen13

.flake8

@@ -6,5 +6,5 @@ per-file-ignores =
     proton_driver/bufferedwriter.pyx: E225, E226, E227, E999
     proton_driver/varint.pyx: E225, E226, E227, E999
     # ignore example print warning.
-    example/*: T201,T001
+    example/*: T201, T001, E999
 exclude = venv,.conda,build

.github/workflows/test.yml

@@ -41,6 +41,9 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
           architecture: x64
+        env:
+          if: ${{ matrix.python-version == 3.5 }}
+          PIP_TRUSTED_HOST: "pypi.python.org pypi.org files.pythonhosted.org"
 #      - name: Login to Docker Hub
 #        uses: docker/login-action@v1
 #        with: