There's actually no reason to believe that Diamond Pythons need UV any more than other snakes, which is to say that it's highly unlikely. Diamonds are only a regional Carpet variation, and being, together with the SW Carpet, the most southern of species, are probably kept too warm by those not familiar with the species and the cooler regions they inhabit. They do thrive in outdoor aviaries in appropriate areas, probably because of the greater rang of temperatures they experience throughout the year.
Some very experienced Diamond hands on APS have also suggested the possibility that DPS (Diamond Python Syndrome) may be caused by a pathogen such as a virus, because there seems to some evidence of it being contagious.
UV won't do any harm to snakes, but it's not necessary for good health.
Jamie