 	public init(brokers: [(String, Int32)], clientId: String, nodeId: Int32? = nil, authentication: Authentication = .none) {
         for (ipv4, port) in brokers {
 			let connectionConfig = Connection.Config(host: ipv4, port: port, clientId: clientId, authentication: authentication)
-			self._brokers["\(ipv4):\(port)"] = Broker(connectionConfig: connectionConfig)
+			self.brokers["\(ipv4):\(port)"] = Broker(connectionConfig: connectionConfig)
         }
         self.clientId = clientId
 

        - Parameter callback:
     */
    public func listGroups(_ callback: @escaping (String, String) -> ()) {
        for (_, broker) in _brokers {
            dispatchQueue.async {
                broker.listGroups() { a, b in
                    callback(a, b)

    }
    
    func getGroupCoordinator(groupId: String, callback: @escaping (Broker) -> Void) {
        brokers.first?.value.getGroupCoordinator(groupId: groupId) { response in
            let host = response.host
            let port = response.port
            
