Radiator fan running
 

I bought a brand new i30 'Go Forward' model picked it up Friday, so only 2.5 days ago. Ive noticed when I turn the car off after parking the radiator fan keeps running for about 20-30 seconds, its been doing that since Saturday morning I cant remember it doing it after I picked it up Friday. Should it be doing it? Is there something Im supposed to do to stop it?