I apologize that no one has responded to your question sooner. Different experts come online at various times. I just came online and saw your question. My name is ***** ***** I’m a biologist with a special interest in reptiles. I'm sorry to hear of this problem.
From your description, it sounds like your snake may have vesicular dermatitis, also caused blister disease. Those fluid pockets you see can be signs of this. It can be caused by too much humidity, a damp substrate, mites, or the salmonella bacteria. If not treated promptly, septicemia (blood poisoning) can result. Your snake will need to be seen by a reptile vet. This link will take you to a directory of herp vets:
I’ll also give you some first aid measures you can take. You can treat the snake’s skin with Betadine, or give him a soak in a shallow Betadine/water bath. Betadine is available in the first aid department of discount stores and pharmacies. Follow that with an application of plain Neosporin. Repeat twice a day until you can get to the vet. You’ll also need to remove all substrate and replace it with plain paper. You can read more about vesicular dermatitis at these sites:
This is an iguana site, but the information still applies. Scroll down to ‘Vesicular Dermatitis.’
If you have more questions, let me know in a REPLY. I hope your python will reach a full recovery.
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