human
Solve the following python programming problem given the following code:
@ mock.patch.object (action_db_util, 'get_action_by_ref', mock.MagicMock (return_value = ACTION_1)) 
@ mock.patch.object (action_service, 'request', return_value = (DummyActionExecution (), None)) 
def test_chain_runner_task_is_canceled_while_running(self, request) : 
    chain_runner = acr.get_runner () 
    chain_runner.entry_point = CHAIN_2_PATH 
    chain_runner.action = ACTION_1 
    original_run_action = chain_runner._run_action 
    def mock_run_action(* args, **kwargs) : 
        original_live_action = args [0] 
        if (original_live_action.action == 'wolfpack.a2') : 
            status = LIVEACTION_STATUS_CANCELED 
else : 
            status = LIVEACTION_STATUS_SUCCEEDED 
request.return_value = (DummyActionExecution (status = status), None) 
        liveaction = original_run_action (* args, ** kwargs) 
        return liveaction 
chain_runner._run_action = mock_run_action 
    action_ref = ResourceReference.to_string_reference (name = ACTION_1.name, pack = ACTION_1.pack) 
    chain_runner.liveaction = LiveActionDB (action = action_ref) 
    chain_runner.container_service = RunnerContainerService () 
    chain_runner.pre_run () 
    (status, _, _) = chain_runner.run ({ 
        
}) 
    self.assertEqual (status, LIVEACTION_STATUS_CANCELED) 
    self.assertNotEqual (mock_run_action.chain_holder.actionchain, None) 
    self.assertEqual (request.call_count, 2) 

    
    

    Fix the buggy line: self.assertNotEqual (mock_run_action.chain_holder.actionchain, None)
assistant
#Here is Python program to fix the buggy line: self.

self.assertNotEqual (chain_runner.chain_holder.actionchain, None)