code: def test_circular_list(self):
      lst = []
      lst.append(lst)
      self.assertRaises(ValueError, json.dumps, lst)
  
file_path: catboost/contrib/python/simplejson/py2/simplejson/tests/test_check_circular.py
imports: from unittest import TestCase
  import simplejson
label_desc: Use image node_id 2 for calling the TestCheckCircular obj's underlying member method code with example usage: obj.test_circular_list() without return types