A simple ikea/brio railroad self-moving locomotive

A simple loco made from simple geared motor (1$ here https://ru.aliexpress.com/item/TT-Motor-Smart-Car-Robot-Gear-Motor-for-Arduino-Free-Shipping-Wholesale/32642267017.html). Vitamins are 18350 or CR123A battery, magnet, 2 pcs M3x25 screw, battery spring and some wires. https://www.youtube.com/watch?v=Q5KFoAS8Tfg&feature=youtu.be .