code: def testChildClasses(self):
      with ChildMyContext() as ctx:
          self.assertEqual(ChildMyContext.current(), ctx)
          self.assertEqual(MyContext.current(), ctx)
  
file_path: pytorch/caffe2/python/context_test.py
imports: from caffe2.python import context, test_util
  from threading import Thread
label_desc: Use image node_id 7 for calling the TestContext obj's underlying member method code with example usage: obj.testChildClasses() without return types