luhn-generator/update/node_modules/core-js/modules/_uid.js

A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

var id = 0;
var px = Math.random();
module.exports = function (key) {
  return 'Symbol('.concat(key === undefined ? '' : key, ')_', (++id + px).toString(36));
};