Ah, that's a tricky one. Stucco can be difficult to work with since it's not as smooth as other surfaces. But don't worry, there are a few ways you can still attach those Christmas lights! One option is to use a self-adhesive hook or hook-and-loop fastener. You can just stick the hook onto the stucco and then hang the lights from the hook. Another option is to use a nail or screw to attach the lights to the stucco directly. Just make sure to use small screws or nails so you don't damage the stucco too much.