code: def test_getMultImageDataByIds_given_empty_idList(self):
      returnedImageDatas: Dict[
          str, ImageData
      ] = self.imageDataExtractor.getMultImageDataByIds(ids=[])
      self.assertEqual(0, len(returnedImageDatas))
  
imports: import sys
  import unittest
  from typing import Dict, List
  from MONAILabelReviewerLib.ImageData import ImageData
  from MONAILabelReviewerLib.ImageDataExtractor import ImageDataExtractor
  from MONAILabelReviewerLib.MONAILabelReviewerEnum import Level, SegStatus
label_desc: Use image node_id 27 for calling the ImageDataExtractorTest obj's underlying member method code with example usage: obj.test_getMultImageDataByIds_given_empty_idList() without return types