How do I detect captive portals and network changes in Swift?

import Network

class NetworkMonitor {
    let monitor = NWPathMonitor()
    var isConnected = false
    var isExpensive = false

    init() {
        monitor.pathUpdateHandler = { path in
            self.isConnected = path.status == .satisfied
            self.isExpensive = path.isExpensive
            
            if self.isConnected {
                print("Network is available")
                if self.isExpensive {
                    print("Network is expensive")
                }
            } else {
                print("No network connection")
            }
        }

        let queue = DispatchQueue(label: "Monitor")
        monitor.start(queue: queue)
    }
}

let networkMonitor = NetworkMonitor()