I got two different failure modes for
https://chromium-review.googlesource.com/c/infra/luci/luci-py/+/815495


https://logs.chromium.org/v/?s=infra%2Fbuildbucket%2Fcr-buildbucket.appspot.com%2F8960816346209317168%2F%2B%2Fsteps%2Fpresubmit%2F0%2Fstdout
      logservice = apiproxy_stub_map.apiproxy.GetStub('logservice')
  AttributeError: 'module' object has no attribute 'apiproxy'


https://logs.chromium.org/v/?s=infra%2Fbuildbucket%2Fcr-buildbucket.appspot.com%2F8960815865857215040%2F%2B%2Fsteps%2Fpresubmit%2F0%2Fstdout
  16908 2017-12-08 01:41:10.306 W: Got a reply with HTTP status code 401 for http://localhost:9050/swarming/api/v1/bot/task_update/3a4c99ff0802e811 on attempt 0.
  401 Client Error: Unauthorized for url: http://localhost:9050/swarming/api/v1/bot/task_update/3a4c99ff0802e811