human
Solve the following python programming problem given the following code:
def _checkin_event_fixture(self) : 
    p = self._queuepool_fixture () 
    canary = [] 
    def checkin(* arg, **kw) : 
        canary.append ('checkin') 
event.listen (p, 'checkin', p) 
    return (p, canary) 

    
    

    Fix the buggy line: event.listen (p, 'checkin', p)
assistant
#Here is Python program to fix the buggy line: event.

event.listen (p, 'checkin', def checkin()