Personally I wouldn't want to leave mine alone for more than a weekend, but I am a beginner, so you might want a more experienced opinion.

Is there someone who can check on them? Doesn't have to be a snake lover, just someone you trust who can go to your place every other day to make sure temps are ok and refill water dishes (maybe with a watering can if they are squeamish) and give you a call if something is off.