Based on research currently available, I personally don't believe that BPs are capable of having a personality. With that said I have observed on many occasions different behaviors of my BPs.
Here's an interesting study that I interpret suggests that Ball Pythons in captivity may have larger brains than in the wild. However, they were testing juvenile BPs and are following their progress: https://jeb.biologists.org/content/221/7/jeb180281