code: def test_mapnode_iterfield_check():
      mod1 = pe.MapNode(
          EngineTestInterface(), iterfield=["input1"], name="mod1"
      )
      with pytest.raises(ValueError):
          mod1._check_iterfield()
      mod1 = pe.MapNode(
          EngineTestInterface(),
          iterfield=["input1", "input2"],
          name="mod1",
      )
      mod1.inputs.input1 = [1, 2]
      mod1.inputs.input2 = 3
      with pytest.raises(ValueError):
          mod1._check_iterfield()
  
imports: import os
  from copy import deepcopy
  import pytest
  from ....None import config
  from ....interfaces import utility
  from ....interfaces import base
  from ...None import engine
  from ..utils import merge_dict
  from .test_base import EngineTestInterface
  from .test_utils import UtilsTestInterface
label_desc: Use image node_id 3 for calling a global function with example usage: test_mapnode_iterfield_check() without return types