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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(self):
 """EventSourceResponse object is used for streaming data to the client, this method returns future, so we can wain until connection will be closed or other task explicitly call ``stop_streaming`` method. """

        if self._ping_task is None:
            raise RuntimeError('Response is not started')
        with contextlib.suppress(asyncio.CancelledError):
            await self._ping_task