Pick the snake up, look it square in the eye, and say "It's FOOD! You put it in your mouth and swallow it! Is that so hard? What's WRONG with you??" Then you eat a couple of pinks in front of them so they get the idea. Seriously, I'm in the same boat you are, except with couple of Kenyans, and it's no fun! Of course, in my case, the one weighs 5 grams and hasn't eaten voluntarily since early February or before. Just keep trying! And don't panic too bad until they lose 20% of their body weight, as a general rule.