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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 _disconnect(self):
 """ Disconnect only, without closing the session. Used in reconnections to different data centers, where we don't want to close the session file; user disconnects however should close it since it means that their job with the client is complete and we should clean it up all. """

        await self._sender.disconnect()
        await helpers._cancel(self._log[__name__],
                              updates_handle=self._updates_handle)