code: def testIt(self):
      class B(A):
          def f(self):
              return 10
  
      a = New()  # this must work
      b = B()
      self.assertEqual(Call(a), 0)
      self.assertEqual(Call(b), 10)
  
      def fails():
          Fail(A())
  
      self.assertRaises(TypeError, fails)
      self.assertEqual(Fail(a), 0)
  
imports: import unittest
  from register_ptr import *
label_desc: Use image node_id 1 for calling the RegisterPtrTest obj's underlying member method code with example usage: obj.testIt() and returns: int