player = Player()
key = Item('key', 'unlock')
player.pickUp(key)
printNow(player.listItems())
printNow("There is a locked door in front of you")
choice = requestString("What would you like to do: ")
if choice.lower() == 'use key': if player.useItem('key') == 'unlock': printNow("You have unlocked the door")
Etc.