public bool UpdateBank(string id, Bank bank)
        {
            int index = _banks.FindIndex(r => r.BIC == bank.BIC);
            if (index == -1)
                return false;

            _banks.RemoveAt(index);
            _banks.Add(bank);

            return true;
        }
 public void AddBank(Bank bank)
 {
     _banks.Add(bank);
 }