Anti Lockout Device (Print in place)

This Model is print in place. On the backside you will find a notch that you can use to get it free with a coin. also Adding some oil will help taht it can move free.

Attack it with doubblesided tape to your doorframe. You hang your keys there and as soon as the door opens the wheight of the key will pull it down and the bar go in between the doorframe and the door so it cannot be closed anymore until you want it.