_iterate (fn, endEarly = false) {
    for (const key in store) {
      if (Object.prototype.hasOwnProperty.call(store, key)) {
        const player = store[key]

        if (endEarly) {
          if (fn(player)) {
            break
          }
        } else {
          fn(player)
        }
      }
    }
  }
@private
@param {IterateFunction} fn
@param {?boolean} endEarly