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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:
 async def wait_until_serving(self) -> None: """ Await until the ``Endpoint`` is ready to receive events. """

        await asyncio.gather(
            self._receiving_loop_running.wait(),
            self._internal_loop_running.wait(),
            loop=self.event_loop
        )