Converting LED fairy lights to USB power

Sponsored by https://PCBWay.com ~~~ A relatively simple project today. I convert a string of 80 LED fairy lights from battery power to USB power, using an old iPhone Lightning cable. I add an inline switch and reduce the luminosity with a through-hole resistor and a calculator. Should be a quick one, right..? ~~~ PCBWay offer PCB manufacture, CNC machining, sheet metal fabrication, 3D printing and injection moulding and check out their great library of community contributed projects and ready-to-order modules: https://PCBWay.com ~~~ The lights I bought https://www.ebay.co.uk/itm/354235013712 My PCBWay projects page https://www.pcbway.com/project/member...