public WarehouseAndPack findWarehouseAndPack(
     Drone drone, Order order, List<Warehouse> warehouses) {
   for (Warehouse warehouse : warehouses) {
     Pack pack = warehouse.buildPartialPack(order, drone);
     if (pack.getWeight() == order.pack.getWeight()) {
       return new WarehouseAndPack(warehouse, pack);
     }
   }
   return null;
 }