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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_rm_ha(self, new_rm_host_id, zk_service_name=None):
 """ Enable high availability for a YARN ResourceManager. @param new_rm_host_id: id of the host where the second ResourceManager will be added. @param zk_service_name: Name of the ZooKeeper service to use for auto-failover. If YARN service depends on a ZooKeeper service then that ZooKeeper service will be used for auto-failover and in that case this parameter can be omitted. @return: Reference to the submitted command. @since: API v6 """

    args = dict(
      newRmHostId = new_rm_host_id,
      zkServiceName = zk_service_name
    )
    return self._cmd('enableRmHa', data=args)