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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 restore_event(self, requestId):
 """restore an event based on the requestId. For example if the user app had to shutdown with pending requests. The user can rebuild the Events they were waiting for based on the requestId(s). """

        with self.__requests:
            if requestId not in self.__requests:
                self.__requests[requestId] = RequestEvent(requestId)
                return True
        return False