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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 _peek_async_request(self, msg_id, msg_name):
 """Peek at the set of callbacks for a request. Return tuple of Nones if callbacks don't exist. """

        assert get_thread_ident() == self.ioloop_thread_id
        if msg_id is None:
            msg_id = self._msg_id_for_name(msg_name)
        if msg_id in self._async_queue:
            return self._async_queue[msg_id]
        else:
            return None, None, None, None, None