code: def loadJsonStr(self, fileName: str) -> str:
      with open(
          os.path.join(sys.path[0], "TestDataSet/" + fileName)
      ) as f:
          data = json.dumps(json.load(f))
      return data
  
imports: import json
  import os
  import sys
  import unittest
  from MONAILabelReviewerLib.ImageData import ImageData
  from MONAILabelReviewerLib.JsonParser import JsonParser
  from MONAILabelReviewerLib.SegmentationMeta import SegmentationMeta
label_desc: Use image node_id 3 for calling the ImageDataTest obj's underlying member method code with example usage: obj.loadJsonStr(fileName) and returns: data