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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 disable_nn_ha(self, active_name, snn_host_id, snn_check_point_dir_list, snn_name=None):
 """ Disable high availability with automatic failover for an HDFS NameNode. @param active_name: Name of the NamdeNode role that is going to be active after High Availability is disabled. @param snn_host_id: Id of the host where the new SecondaryNameNode will be created. @param snn_check_point_dir_list : List of directories used for checkpointing by the new SecondaryNameNode. @param snn_name: Name of the new SecondaryNameNode role (Optional). @return: Reference to the submitted command. @since: API v6 """

    args = dict(
      activeNnName = active_name,
      snnHostId = snn_host_id,
      snnCheckpointDirList = snn_check_point_dir_list,
      snnName = snn_name
    )
    return self._cmd('hdfsDisableNnHa', data=args, api_version=6)