I added a low wattage UVB bulb on an 8 hr timer daytime only, and here’s my results.

[Shadowy]

Correct me if I’m wrong.
I know ball pythons don’t NEED uvb by any means. However I know it doesn’t hurt them either. Some studies say it increases activity and color. I decided to give it a shot. This is the first day I’ve used a 26W 5% UVB bulb during the day. And I’m already seeing a new behavior. The hide my snake is in is plenty big for her, and she’s normally completely in the hide. Well today I noticed for a brief time she purposely pushed part of her body out of the hide. It appears she’s purposely exposing herself to the UVB light. Definitely interesting and abnormal for her. I’m going to continue using it unless I notice signs of stress. Just thought I’d share my findings.

[Bogertophis]

Can't rule out a coincidence... but who knows?

I happen to think that occasional exposure to real outdoor sunshine (within acceptable temperature range, of course) also
positively affects our snakes, with increased appetite. Real sun is far more effective than any bulb, but better than nothing.

[Starscream]

I've used UVB on my ball python for over a year, and I can confirm that she does stick parts of her body out of hides while it's on, though not every single day. Just yesterday she was sticking her neck out and hiding her eyes under a leaf. It was pretty adorable. About 3 hours of purposeful exposure that I observed, though she was already out neck-basking when I walked in the room.

Obligatory crappy through-the-tub photo of said neck-basking.