code: def test_strict_get_single_artifact(self):
      self.assertArtifactEqual(
          self._environ.strict_get("single_artifact_input", _Example),
          self._single_artifact_input[0],
      )
      self.assertArtifactEqual(
          self._environ.strict_get("single_artifact_output", _Example),
          self._single_artifact_output[0],
      )
  
imports: from typing import Any, Callable, List, Optional, Type, Union
  from absl.testing import parameterized
  import tensorflow
  from tfx.orchestration.experimental.core import test_utils
  from tfx.orchestration.portable import data_types
  from tfx.orchestration.portable import execution_environ
  from tfx.proto.orchestration import pipeline_pb2
  from tfx.types import artifact
  from tfx.types import standard_artifacts
  from tfx.utils.di import errors
label_desc: Use image node_id 2 for calling the ExecutionEnvironTest obj's underlying member method code with example usage: obj.test_strict_get_single_artifact() without return types