If you take the light bulb out of the socket and have some type of heat (as stated by boosting98) a blow dryer or something along those lines will work, but it's nearly impossible to get it completely out, or if you can find something bendable possibly attach some type of cloth to the end of it and use the bulb socket to get into the headlight.

Other than that I'm not sure if there's any advice I can give other than to just replace the light (nice halos usually do the trick ).