function that put OSX to sleep after some seconds/minutes/hours. I use it when I am listening music at night

sleep_after.sh

sleep_after() {
    local sleep_time=$1;

    if [[ $2 = "hour" ]] then 
        sleep_time=$(($sleep_time*60*60));
    elif [[ $2 = "min" ]] then
        sleep_time=$(($sleep_time*60));
    elif [[ !$2 ]] then
        echo "options is not valid: $2";
        return 0;
    fi

    sleep $sleep_time;
    osascript -e 'tell application "Finder" to sleep';
}

You can use it like this:
sleep_after <number> <hour/min>(optional)

sleep_after 10 # it will be in seconds
sleep_after 10 min
sleep_after 1 hour