!afk command

i think if we make a command for !afk it will be good for players that want to stay in the server, but not get punished for farming hours illegally. My concept is that it will pause the time gained for them, and make them invincable, but as soon as they move it will be removed, and you can only use the command 2 minutes apart if you have just got out, for cheating reasons. thanks for your time!