code: def test_roundtrip(self):
      s = writes(nb0)
      #        print
      #        print pprint.pformat(nb0,indent=2)
      #        print
      #        print pprint.pformat(reads(s),indent=2)
      #        print
      #        print s
      self.assertEqual(reads(s), nb0)
  
file_path: nbformat/tests/v2/test_json.py
imports: from __future__ import annotations
  from unittest import TestCase
  from nbformat.v2.nbjson import reads, writes
  from .nbexamples import nb0
label_desc: Use image node_id 1 for calling the TestJSON obj's underlying member method code with example usage: obj.test_roundtrip() without return types