code: def testExplicitServe(self):
      tb = program.TensorBoard(
          plugins=[core_plugin.CorePluginLoader],
          assets_zip_provider=fake_asset_provider,
          subcommands=[_TestSubcommand()],
      )
      tb.configure(
          ("tb", "serve", "--logdir", "logs", "--path_prefix", "/x///")
      )
      tb.main()
      program.TensorBoard._run_serve_subcommand.assert_called_once()
      flags = program.TensorBoard._run_serve_subcommand.call_args[0][0]
      self.assertEqual(flags.logdir, "logs")
      self.assertEqual(flags.path_prefix, "/x")
  
imports: import argparse
  import io
  import sys
  from unittest import mock
  from tensorboard import program
  from tensorboard import test
  from tensorboard.plugins import base_plugin
  from tensorboard.plugins.core import core_plugin
label_desc: Use image node_id 4 for calling the SubcommandTest obj's underlying member method code with example usage: obj.testExplicitServe() without return types