GCP Authentication: RefreshError
In order to round-trip test mail sending code in our GCP backend I am sending an email to a GMail inbox and attempting to verify its arrival. The current mechanism for authentication to the GMail API is fairly standard, pasted from the GMail API documentation and embedded in a function: def authenticate(): """Authenticates to the Gmail API using data in credentials.json, returning the service instance for use in queries etc.""" store = file.Storage('token.json') creds = store.get() if not creds or creds.invalid: flow = client.flow_from_clientsecrets(CRED_FILE_PATH, SCOPES) creds = tools.run