如何阻止NSNotification中的Observer调用两次？

func removeObserver(_ observer: Any, forKeyPath keyPath: String)

var hasReceivedNotification = false

func notificationReceived() {
    if !hasReceivedNotification {
        // 执行相关操作
        hasReceivedNotification = true
    }
}

DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
    // 执行相关操作
}

NotificationCenter.default.removeObserver(self)

NotificationCenter.default.addObserver(self, selector: #selector(notificationReceived), name: NSNotification.Name(rawValue: "NotificationName"), object: nil, queue: nil, using: nil)