Data Driven Page Python Export to PDF

[NicolaDickson]

I am currently working with someone to develop a script using python that will export my data driven pages into PDF, while also changing the active layers.  I have a set of background layers that will be on every map, and then a group that will be turned on one at a time and exported. The title of the map is to match the current layer turned on. All other text that changes is set up from the data driven pages.  We have had immense troubles getting this to work. It batches out the first set of data driven pages with the first active layer, but does not seem to turn over to the next active layer. Here is the current script:

Any help would be greatly appreciated.