code: def testCreateAgent(self):
      agent = greedy_multi_objective_agent.GreedyMultiObjectiveNeuralAgent(
          self._time_step_spec,
          self._action_spec,
          self._scalarizer,
          objective_network_and_loss_fn_sequence=self._create_objective_network_and_loss_fn_sequence(),
          optimizer=None,
      )
      self.assertIsNotNone(agent.policy)
      self.assertEqual(len(agent._variables_to_train()), 6)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  from typing import List, Tuple
  import numpy
  import tensorflow
  from tf_agents.bandits.agents import greedy_multi_objective_neural_agent
  from tf_agents.bandits.drivers import driver_utils
  from tf_agents.bandits.multi_objective import multi_objective_scalarizer
  from tf_agents.bandits.networks import global_and_arm_feature_network
  from tf_agents.bandits.networks import heteroscedastic_q_network
  from tf_agents.bandits.specs import utils
  from tf_agents.networks import network
  from tf_agents.policies import utils
  from tf_agents.specs import array_spec
  from tf_agents.specs import tensor_spec
  from tf_agents.trajectories import policy_step
  from tf_agents.trajectories import time_step
  from tf_agents.typing import types
  from tf_agents.utils import common
label_desc: Use image node_id 3 for calling the MultiObjectiveAgentTest obj's underlying member method code with example usage: obj.testCreateAgent() without return types