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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 disconnect_async(self, conn_id, callback):
 """Asynchronously disconnect from a device."""


        future = self._loop.launch_coroutine(self._adapter.disconnect(conn_id))
        future.add_done_callback(lambda x: self._callback_future(conn_id, x, callback))