问错误的NTP日期响应Swift 4

EN

Clock.sync { date, offset in
        let dateFormatter = DateFormatter()
        dateFormatter.calendar = NSCalendar.current
        dateFormatter.timeZone = TimeZone.current
        dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss"

        let dt = dateFormatter.string(from: date!)
        dateFormatter.timeZone = TimeZone(abbreviation: "UTC")

        print(dt)
    }