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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 _async_connect(self):
 # pragma: no cover """ connect and authenticate to the XMPP server. Async mode. """

        try:
            self.conn_coro = self.client.connected()
            aenter = type(self.conn_coro).__aenter__(self.conn_coro)
            self.stream = await aenter
            logger.info(f"Agent {str(self.jid)} connected and authenticated.")
        except aiosasl.AuthenticationFailure:
            raise AuthenticationFailure(
                "Could not authenticate the agent. Check user and password or use auto_register=True")