code: def mocked_file(contents: Dict[Any, Any]) -> io.IOBase:
      file_object = io.StringIO()
      json.dump(contents, file_object)
      file_object.seek(0)
      return file_object
  
imports: import io
  import json
  import pathlib
  import sys
  import unittest
  from typing import Any, Dict, Set
  from unittest import mock
label_desc: Use image node_id 1 for calling a global function with example usage: mocked_file(contents) and returns: file_object