# File lib/deltacloud/drivers/rhevm/rhevm_client.rb, line 209
    def clusters(opts={})
      headers = {
        :accept => "application/xml; detail=datacenters"
      }
      headers.merge!(auth_header)
      if opts[:id]
        vm = Client::parse_response(RHEVM::client(@api_entrypoint)["/clusters/%s" % opts[:id]].get(headers)).root
        [ RHEVM::Cluster::new(self, vm)]
      else
        Client::parse_response(RHEVM::client(@api_entrypoint)["/clusters"].get(headers)).xpath('/clusters/cluster').collect do |vm|
          RHEVM::Cluster::new(self, vm) if has_datacenter?(vm)
        end.compact
      end
    end