code: def test_req_add_get_executors():
      r = DataRequest()
      r.add_executor("one")
      assert r.last_executor == "one"
      r.add_executor("two")
      assert r.last_executor == "two"
  
      r2 = DataRequest.from_proto(r.proto)
      assert r2.last_executor == "two"
  
imports: import copy
  import pytest
  from docarray import Document, DocumentArray
  from google.protobuf.json_format import MessageToDict, MessageToJson
  from jina.excepts import BadRequestType
  from jina.helper import random_identity
  from jina.proto import jina_pb2
  from jina.proto.serializer import DataRequestProto
  from jina.types.request.data import DataRequest, Response
label_desc: Use image node_id 23 for calling a global function with example usage: test_req_add_get_executors() without return types