这应该是直接使用凭据对象的正确方法：
import gdata.gauthcredentials = SignedJwtAssertionCredentials(serviceEmail,key, sub=adminEmail,scope=scopes)client = gdata.apps.emailsettings.client.EmailSettingsClient(domain='mydomain.co')client.auth_token = gdata.gauth.OAuth2TokenFromCredentials(credentials)client.UpdateForwarding(username=username, enable=True, forward_to=forwardTo, action='ARCHIVE')
