This one is very 'beta', use at your own risk
Creates a dome of lights who's color is based on the texture sampled from a sphere
Set the number of lights - more are neccessary for more detailed lighting, for example if you use a file texture.
Create the Sphere first, adjust its shader/texture to your liking as well as scale.
With the sphere selected, create the lights with 'Add Lights/Remake Lights'. if you change the spheres shader or texture you have to remake the lights.
adjust the 'Intensity Multipyer' to increase or decrease the intensity of all the lights.
A helper node called IBL:HelperNode is created by the script, with all the adjustable attributes, so the script interface is not neccessary to adjust the lights.
This node can be selected by unchecking 'show DAG objects only' in the Outliner.
PS: the code for the mental ray vertex color baking is probably the most interesting part of this mel script and exploring that was one of the main reasons for writing this script