code: def testEnvironmentGCEIPOverride(self):
      self.assertEqual(
          "http://1.2.3.4", client._gce_metadata_endpoint()
      )
  
imports: import datetime
  import json
  import os
  import time
  import urllib
  from absl import flags
  from tensorflow.python.platform import test
  from tensorflow.python.tpu.client import client
label_desc: Use image node_id 7 for calling the CloudTpuClientTest obj's underlying member method code with example usage: obj.testEnvironmentGCEIPOverride() without return types