Provide python impl.

Author: purple4reina

ci/input_files/build.yaml.tpl

@@ -100,6 +100,7 @@ integration-test ({{ $runtime.name }}-{{ $runtime.arch }}):
     - yarn global add serverless@^3.38.0 --prefix /usr/local
     - yarn global add serverless-python-requirements@^6.1.1 --prefix /usr/local
     - cd integration_tests && yarn install && cd ..
+    - alias python=python3
   script:
     - RUNTIME_PARAM={{ $runtime.python_version }} ARCH={{ $runtime.arch }} ./scripts/run_integration_tests.sh