Situation: I am pulling a door while having a vending machine and a lamp on my left.
Alternative situations: Just got some chips from a vending machine in my eight o'clock direction and leaving through the front door now, while a lamp in my ten o'clock direction is blinking. I want to get out of the room through the door on the right side of the lamp.
Question: What can I insert into the vending machine behind me to buy something?