package main

import (
    "fmt"
    "os"
    "time"
)

func main() {
    m := "1s"
    if len(os.Args) > 1 {
        m = fmt.Sprintf("%ss", os.Args[1])
    }
    d, err := time.ParseDuration(m)
    if err != nil {
        fmt.Println("bad time.")
        os.Exit(1)
    }
    time.Sleep(d)
}