code: def test(self):
      addr = "localhost:6806"
      with mock.patch.object(grpc, "secure_channel", autospec=True):
          ingester = server_ingester.ExistingServerDataIngester(
              addr,
              channel_creds_type=grpc_util.ChannelCredsType.LOCAL,
          )
          ingester.start()
      self.assertIsInstance(
          ingester.data_provider, grpc_provider.GrpcDataProvider
      )
  
imports: import os
  import subprocess
  import tempfile
  import threading
  import time
  from unittest import mock
  import grpc
  from tensorboard import test
  from tensorboard.data import grpc_provider
  from tensorboard.data import server_ingester
  from tensorboard.util import grpc_util
label_desc: Use image node_id 1 for calling the ExistingServerDataIngesterTest obj's underlying member method code with example usage: obj.test() without return types