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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 enable_hdfs_auto_failover(self, nameservice, active_fc_name, standby_fc_name, zk_service):
 """ Enable auto-failover for an HDFS nameservice. This command is no longer supported with API v6 onwards. Use enable_nn_ha instead. @param nameservice: Nameservice for which to enable auto-failover. @param active_fc_name: Name of failover controller to create for active node. @param standby_fc_name: Name of failover controller to create for stand-by node. @param zk_service: ZooKeeper service to use. @return: Reference to the submitted command. """

    version = self._get_resource_root().version

    args = dict(
      nameservice = nameservice,
      activeFCName = active_fc_name,
      standByFCName = standby_fc_name,
      zooKeeperService = dict(
        clusterName = zk_service.clusterRef.clusterName,
        serviceName = zk_service.name,
        ),
      )
    return self._cmd('hdfsEnableAutoFailover', data=args)