There are already many ways to build and use light sources in Minecraft. Now here is another one.

The button hanging from the ceiling near the enchantment table is a simple T-flip-flop that turns the lights and pistons on and off.

Instructions:

Here you can still see the wiring: When you press the button from below, the piston with the sand on it briefly extends and retracts, where a signal is generated that causes the other sticky piston to "release" its block and thus then activates the line under which the lamps and pistons are located.