Something like this would probably be easy:

https://www.amazon.com/Brilliant-Evolution-BRRC135-Remote-Night/dp/B01JTA4QXI/ref=sr_1_3?ie=UTF8&qid=1539819510&sr=8-3&keywords=wireless+battery+light

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Obviously, you don't need a pack of them, but the remote is simple. It's an avenue you might try looking down.