code: def _set_required_env_vars(self, env_vars):
      for k, v in env_vars.items():
          self.enter_context(test_case_utils.override_env_var(k, v))
  
imports: import json
  import os
  from unittest import mock
  import tensorflow
  from tfx.dsl.io import fileio
  from tfx.orchestration import metadata
  from tfx.orchestration.kubeflow import container_entrypoint
  from tfx.orchestration.kubeflow import kubeflow_dag_runner
  from tfx.orchestration.kubeflow.proto import kubeflow_pb2
  from tfx.orchestration.portable import beam_executor_operator
  from tfx.orchestration.portable import data_types
  from tfx.orchestration.portable import execution_publish_utils
  from tfx.orchestration.portable import launcher
  from tfx.orchestration.portable import outputs_utils
  from tfx.orchestration.portable import python_driver_operator
  from tfx.orchestration.portable.mlmd import execution_lib
  from tfx.proto.orchestration import driver_output_pb2
  from tfx.proto.orchestration import execution_result_pb2
  from tfx.proto.orchestration import pipeline_pb2
  from tfx.types import standard_artifacts
  from tfx.utils import io_utils
  from tfx.utils import test_case_utils
  from google.protobuf import json_format
  from ml_metadata.proto import metadata_store_pb2
label_desc: Use image node_id 1 for calling the MLMDConfigTest obj's underlying member method code with example usage: obj._set_required_env_vars(env_vars) without return types