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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 _add_timeout(self, request, future):
 """Adds a timeout for the given request to the given future."""

        io_loop = IOLoop.current()
        t = io_loop.call_later(
            request.ttl,
            self._request_timed_out,
            request.id,
            request.service,
            request.ttl,
            future,
        )
        io_loop.add_future(future, lambda f: io_loop.remove_timeout(t))