Master Lock claims the lock has "anti-shim" technology, meaning that it would be really hard to pull the shackle loose. Master Lock 4401DLH Bluetooth Padlock (Black) at Amazon for $135.17 ...

They just dump parts in different hoppers and the machine entirely assembles the lock, checks it, puts the tag for the combination, every 2.1 seconds. That's how we keep the world full of Master ...

If you want to make one of these of your own, Kamkar has a shopping list of parts on his website, as well as software for the machine on GitHub. All told the machine only costs around $100.