func isLeapYear(_ year: Int) -> Bool {

    var divBy4:Bool = false
    var divBy100:Bool = false
    var divBy400:Bool = false


    if number(year, isDivisibleBy: 4) {
        return divBy4 == true
    } else {
        return divBy4 == false
    }

    if number(year, isDivisibleBy: 100) {
        return divBy100 == true
    } else {
        return divBy100 == false
    }

    if number(year, isDivisibleBy: 400) {
        return divBy400 == true } else {
            return divBy400 == false
        }

    if divBy4 && !divBy100 && divBy400 {
        return true
    } else {
        return false
    }









}