The Philadelphia Zoo has a BP said to be 38 years old. So, I guess all of the above is true. Of course, it’s also true that people can live 80, 100 or 120 years. My experience has been that 15-20 is a reasonable expectation for a python life span. I’ve only had a few that broke the 20 year mark, but had quite a few more pythons (carpets and bloods/short tails) that lived to their late teens.