Days between two dates

yourbasic.org/golang
func main() {
    // The leap year 2000 had 366 days.
    t1 := Date(2000, 1, 1)
    t2 := Date(2001, 1, 1)
    days := t2.Sub(t1).Hours() / 24
    fmt.Println(days) // 366
}

func Date(year, month, day int) time.Time {
    return time.Date(year, time.Month(month), day, 0, 0, 0, 0, time.UTC)
}