human
Solve the following python programming problem given the following code:
@ pytest.inlineCallbacks 
def test_node_functions(self) : 
    self.q = Queue.Queue () 
    def cb(key, value) : 
        self.q.put ({ 
            'key' : key, 
            'value' : value, 
}) 
(yield threads.defer_to_thread (time.sleep, 2)) 
    node = TestNode ('127.0.0.1:5000') 
    (yield threads.defer_to_thread (self.storage.add_node, self, cb = CalvinCB (cb))) 
    (yield threads.defer_to_thread (time.sleep, 2)) 
    value = self.q.get (timeout = 0.2) 
    assert (value ['value'] is True) 
    (yield threads.defer_to_thread (self.storage.get_node, node.id, cb = CalvinCB (cb))) 
    (yield threads.defer_to_thread (time.sleep, 2)) 
    value = self.q.get (timeout = 0.2) 
    assert (value ['value'] == { 
        'uri' : node.uri, 
}) 
    (yield threads.defer_to_thread (self.storage.delete_node, node, cb = CalvinCB (cb))) 
    (yield threads.defer_to_thread (time.sleep, 2)) 
    value = self.q.get (timeout = 0.2) 
    assert (value ['value'] is True) 
    (yield threads.defer_to_thread (self.storage.get_node, node.id, cb = CalvinCB (cb))) 
    (yield threads.defer_to_thread (time.sleep, 2)) 
    value = self.q.get (timeout = 0.2) 
    assert (value ['value'] is None) 

    
    

    Fix the buggy line: (yield threads.defer_to_thread (self.storage.add_node, self, cb = CalvinCB (cb)))
assistant
#Here is Python code to fix the buggy line: (yield threads.

(yield threads.defer_to_thread (self.storage.add_node, node, cb = CalvinCB (cb)))