new_contents: from __future__ import print_function
  
  import unittest
  
  import wrapt
  
  class Class(object):
      def __init__(self, value):
          self.value = value
  
  class TestAttributeProxy(unittest.TestCase):
  
      def test_wrap_attribute(self):
          wrapt.wrap_object_attribute(__name__, 'Class.value', wrapt.ObjectProxy)
  
          instance = Class(1)
  
          self.assertEqual(instance.value, 1)
          self.assertTrue(isinstance(instance.value, wrapt.ObjectProxy))
  
          instance.value = 2
  
          self.assertEqual(instance.value, 2)
          self.assertTrue(isinstance(instance.value, wrapt.ObjectProxy))
  
subject: Test for wrapping attribute access. #20