code: def testMakeProtoPlaceholder_MapFieldScalarValue(self):
      actual = resolve(
          _ExecutionInvocation(
              extra_flags={
                  "fookey": "foovalue",
                  "barkey": "barvalue",
              }
          )
      )
      self.assertProtoEquals(
          """
          extra_flags {
            key: "fookey"
            value: "foovalue"
          }
          extra_flags {
            key: "barkey"
            value: "barvalue"
          }
          """,
          parse_text_proto(actual),
      )
  
imports: import base64
  import functools
  from typing import Any, Dict, Optional, Type, TypeVar
  import tensorflow
  from tfx.dsl.compiler import placeholder_utils
  from tfx.dsl.placeholder import placeholder
  from tfx.dsl.placeholder import proto_placeholder
  from tfx.orchestration.portable import data_types
  from tfx.proto.orchestration import execution_invocation_pb2
  from tfx.proto.orchestration import pipeline_pb2
  from google.protobuf import message
  from google.protobuf import text_format
  from ml_metadata.proto import metadata_store_pb2
label_desc: Use image node_id 29 for calling the ProtoPlaceholderTest obj's underlying member method code with example usage: obj.testMakeProtoPlaceholder_MapFieldScalarValue() without return types