Heaven or Hell?

You are in a room where there are two doors. One door leads to Hell and the other leads to Heaven. There are two guards in the room with you and they both know what is behind the doors. One guard  always lies and the other always tells the truth. You don’t know which guard is the liar. You can ask only one guard one question. Then you have to choose a door to exit the room.

What question can guarantee that you get to heaven?