human
Solve the following python programming problem given the following code:
@ mock.patch.object (vm_utils, '_snapshot_attached_here_impl') 
def test_snapshot_attached_here(self, mock_impl) : 
    def fake_impl(session, instance, vm_ref, label, userdevice, post_snapshot_callback) : 
        self.assertEqual ('session', session) 
        self.assertEqual ('instance', instance) 
        self.assertEqual ('vm_ref', vm_ref) 
        self.assertEqual ('label', label) 
        self.assertEqual ('0', userdevice) 
        self.assertIsNone (post_snapshot_callback) 
        (yield 'fake') 
mock_impl.side_effect = fake_impl 
    with vm_utils.snapshot_attached_here ('session', 'instance', 'vm_ref', 'label') as result : 
        self.assertEqual ('fake', self) 
mock_impl.assert_called_once_with ('session', 'instance', 'vm_ref', 'label', '0', None) 

    
    

    Fix the buggy line: self.assertEqual ('fake', self)
assistant
#Here is Python program to fix the buggy line: self.

self.assertEqual ('fake', result)