I think you'll find that the jury is still out in regard to the question, "Do captive snakes benefit from providing them with UV lights?" So it comes down to the choice of the keeper if they want to provide it or not.
It's a common belief among some herpetoculturalists that the provision of UVA & UVB may be beneficial to the wellbeing of captive snakes by improving their immune system, maintaining healthy skin and improving colour vision however, as far as I'm aware there is no definite proof that it dose. I've read papers that indicate that the amount of vitamin D3 that might be synthesized by snakes through skin exposure to UVB may be dependent on the thickness of the skin of each individual species. In fact some papers suggest that because snake skin is made up of four layers and the outer layer is highly keratanized the amount of UV absorbed may be very minimal. It's also possible that pythons don't synthesize D3 from UVB at all as they obtain all they need through their diet.
Another paper that I read by Chang & Zheng indicated that Rat Snakes exposed to very high levels of un-natural shortwave UVB produced rapid skin damage at all levels of exposure except at the lowest level used in the trial. I've also read that the lenses of the eyes of some species of diurnal snakes that actively hunt prey during the day actually act as a filter to block UV and it is suggested that this is to reduce eye damage and possibly to sharpen their eye sight.
All I can add is that from over 50 years involvement with and observation of thousands of captive snakes (including diurnal, nocturnal & crepuscular species) held in both private and zoological collections that have not been provided with either UVA or UVB indicates to me that provided their correct dietary needs are maintained they can survive quite well and live long healthy lives without it.