问如何在Google和本地开发服务器中使用私钥文件和模拟用户(DWD)的服务帐户？

EN

# as suggested by almost all docs, but this isn't everything we need:
google-api-python-client==1.6.5
google-auth==1.4.0
google-auth-httplib2==0.0.3

env_variables:
  # enable socket support of paid app, needed for OAuth2 service-accounts
  # see google-auth documentation, v1.4.1, chapter 1.2.4
  GAE_USE_SOCKETS_HTTPLIB : true
# some other stuff
libraries:
# to make HTTPS calls to other services, needed for OAuth2 service-accounts
# see google-auth documentation, v1.4.1, chapter 1.2.4
- name: ssl
  version: latest

from google.oauth2 import service_account
SCOPES = ["https://www.googleapis.com/auth/spreadsheets"]
APP_ROOT_DIR = os.path.abspath(os.path.dirname(__file__))
SERVICE_ACCOUNT_FILE = "service-account-private-key.json"
import googleapiclient.discovery
credentials = service_account.Credentials.from_service_account_file(SERVICE_ACCOUNT_FILE, scopes=SCOPES)
# impersonate as user@example.com (G Suite domain account)
credentials = credentials.with_subject('user@example.com')
service = googleapiclient.discovery.build('sheets', 'v4', credentials=credentials)
# until here, the code works in production and local dev server
result = service.spreadsheets().values().get(spreadsheetId="DOC-ID-HERE", range="A1:C5").execute()
# execute() will work only in production,
# on local dev, it will raise an ResponseNotReady exception

ERROR    2018-03-05 16:32:03,183 wsgi.py:263] 
Traceback (most recent call last):
  File "/Users/user/google-cloud-sdk/platform/google_appengine/google/appengine/runtime/wsgi.py", line 240, in Handle
    handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
  File "/Users/user/google-cloud-sdk/platform/google_appengine/google/appengine/api/lib_config.py", line 351, in __getattr__
    self._update_configs()
  File "/Users/user/google-cloud-sdk/platform/google_appengine/google/appengine/api/lib_config.py", line 287, in _update_configs
    self._registry.initialize()
  File "/Users/user/google-cloud-sdk/platform/google_appengine/google/appengine/api/lib_config.py", line 160, in initialize
    import_func(self._modname)
  File "/Users/user/git/project/gae/appengine_config.py", line 143, in <module>
    spreadsheetId=spreadsheetId, range=rangeName).execute()
  File "/Users/user/git/project/gae/_lib/oauth2client/_helpers.py", line 133, in positional_wrapper
    return wrapped(*args, **kwargs)
  File "/Users/user/git/project/gae/_lib/googleapiclient/http.py", line 839, in execute
    method=str(self.method), body=self.body, headers=self.headers)
  File "/Users/user/git/project/gae/_lib/googleapiclient/http.py", line 166, in _retry_request
    resp, content = http.request(uri, method, *args, **kwargs)
  File "/Users/user/git/project/gae/_lib/google_auth_httplib2.py", line 187, in request
    self._request, method, uri, request_headers)
  File "/Users/user/git/project/gae/_lib/google/auth/credentials.py", line 121, in before_request
    self.refresh(request)
  File "/Users/user/git/project/gae/_lib/google/oauth2/service_account.py", line 322, in refresh
    request, self._token_uri, assertion)
  File "/Users/user/git/project/gae/_lib/google/oauth2/_client.py", line 145, in jwt_grant
    response_data = _token_endpoint_request(request, token_uri, body)
  File "/Users/user/git/project/gae/_lib/google/oauth2/_client.py", line 106, in _token_endpoint_request
    method='POST', url=token_uri, headers=headers, body=body)
  File "/Users/user/git/project/gae/_lib/google_auth_httplib2.py", line 116, in __call__
    url, method=method, body=body, headers=headers, **kwargs)
  File "/Users/user/git/project/gae/_lib/httplib2/__init__.py", line 1659, in request
    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
  File "/Users/user/git/project/gae/_lib/httplib2/__init__.py", line 1399, in _request
    (response, content) = self._conn_request(conn, request_uri, method, body, headers)
  File "/Users/user/git/project/gae/_lib/httplib2/__init__.py", line 1355, in _conn_request
    response = conn.getresponse()
  File "/Users/user/google-cloud-sdk/platform/google_appengine/google/appengine/dist27/python_std_lib/httplib.py", line 1121, in getresponse
    raise ResponseNotReady()