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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def process_default(self, event):
 """ Processes |event|. """

        self._stats_lock.acquire()
        try:
            events = event.maskname.split('|')
            for event_name in events:
                count = self._stats.get(event_name, 0)
                self._stats[event_name] = count + 1
        finally:
            self._stats_lock.release()