My shaver is plugged in a socket controlled by a switch that also controls the light, and every other time I started a cleaning cycle someone would go to the bathroom and turn off the lights, thus interrupting the cleaning cycle (half of the time it would be me forgetting the shaver is being cleaned). I needed a way to temporarily lock the switch, and also act as a reminder the light was on for a reason, and all the switch locks I found were permanent.

This switchable switch lock is very easy to print and install (you will need longer switch plate screws though) and I'm pretty pleased how it turned out considering it's my first design.