code: def add_hosts(self, hostIds):
      
      hostRefList = [ApiHostRef(self._get_resource_root(), x) for x in hostIds]
      return self._post("hosts", ApiHostRef, True, data=hostRefList,
          api_version=3)
docs: Adds a host to the cluster.
  
      @param hostIds: List of IDs of hosts to add to cluster.
      @return: A list of ApiHostRef objects of the new
               hosts that were added to the cluster
      @since: API v3