code: def setUp(self):
      super().setUp()
      self.init_mlmd()
  
      self.model_1 = self.prepare_tfx_artifact(test_utils.Model)
      self.model_2 = self.prepare_tfx_artifact(test_utils.Model)
      self.model_3 = self.prepare_tfx_artifact(test_utils.Model)
  
      self.artifacts = [self.model_1, self.model_2, self.model_3]
  
imports: from typing import Dict, List, Optional
  from absl.testing import parameterized
  import tensorflow
  from tfx import types
  from tfx.dsl.input_resolution import resolver_op
  from tfx.dsl.input_resolution.ops import latest_policy_model_op
  from tfx.dsl.input_resolution.ops import ops
  from tfx.dsl.input_resolution.ops import test_utils
  from tfx.orchestration.portable.input_resolution import exceptions
  from ml_metadata.proto import metadata_store_pb2
label_desc: Use image node_id 3 for calling the LatestPolicyModelOpTest obj's underlying member method code with example usage: obj.setUp() without return types