Hi Cynthia,
By HTML I'm going to assume you meant XML, as HTML would not be a suitable means for storing holiday schedules.
However, even XML is not best solution in my opinion, and I would steer your towards a 100% scripted example.
Here is a post I made not too long ago, answering this question with a working solution posted for your to review. Just type the variables and steps exactly like you see them in to your script editor and test. Post back if you have any issues getting it to work.
https://supportforums.cisco.com/message/3759523#3759523
Good luck and happy holiday...scripting!
Anthony Holloway
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