def issuers(payment_method)
      if payment_method != PaymentMethod::IDEAL && payment_method != PaymentMethod::IDEAL_PROCESSING
        raise ArgumentError, "Invalid payment method, only iDEAL is supported."
      end

      Ideal::ISSUERS
    end
def issuers(payment_method)
      if payment_method != PaymentMethod::IDEAL && payment_method != PaymentMethod::IDEAL_PROCESSING
        raise ArgumentError, "Invalid payment method, only iDEAL is supported."
      end

      Ideal::ISSUERS
    end
Get a list with payment issuers.