<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def add(self, id, ttl_secs):
 """Adds a new request to the Cemetery that is known to have timed out. The request will be forgotten after ``ttl_secs + ttl_offset_secs`` seconds. :param id: ID of the request :param ttl_secs: TTL of the request (in seconds) """

        ttl_secs = min(ttl_secs + self.ttl_offset_secs, self.max_ttl_secs)
        self._tombstones[id] = IOLoop.current().call_later(
            ttl_secs, self.forget, id,
        )