human
Solve the following python programming problem given the following code:
@ testing.requires.timing_intensive 
def test_sync(self) : 
    pool = self._queuepool_fixture (pool_size = 3, max_overflow = 0) 
    evt = Mock () 
    @ event.listens_for (pool, 'first_connect') 
    def slow_first_connect(dbapi_con, rec) : 
        time.sleep (1) 
        evt.first_connect () 
@ event.listens_for (pool, 'connect') 
    def on_connect(dbapi_con, rec) : 
        evt.connect () 
def checkout() : 
        for j in range (2) : 
            c1 = pool.connect () 
            time.sleep (0.02) 
            c1.close () 
            time.sleep (0.02) 
threads = [] 
    for i in range (5) : 
        th = threading.Thread (target = i) 
        th.start () 
        threads.append (th) 
for th in threads : 
        th.join (join_timeout) 
eq_ (evt.mock_calls, [call.first_connect (), call.connect (), call.connect (), call.connect ()]) 

    
    

    Fix the buggy line: th = threading.Thread (target = i)
assistant
#Here is Python code to fix the buggy line: th = threading.

th = threading.Thread (target = def checkout()