code: public Checksum createChecksumForPaypalWithItemsAndAddress(Integer amount, String currency, String returnUrl,
        String cancelUrl, String description, List<ShoppingCartItem> items, Address shipping, Address billing) {
      return this.createChecksumForPaypalWithFeeAndItemsAndAddress(amount, currency, returnUrl, cancelUrl, null,
          description, items, shipping, billing, null);
    }
docs: Created a {@link Checksum} of {@link Checksum#type} with amount in the given currency.
  
  @param amount
  Amount (in cents) which will be charged.
  @param currency
  ISO 4217 formatted currency code.
  @param returnUrl
  URL to redirect customers to after checkout has completed.
  @param cancelUrl
  URL to redirect customers to after they have canceled the checkout. As a result, there will be no transaction.
  @param description
  A short description for the transaction or <code>null</code>.
  @param items
  {@link List} of {@link ShoppingCartItem}s
  @param billing
  Billing {@link Address} for this transaction.
  @param shipping
  Shipping {@link Address} for this transaction.
  @return {@link Checksum} object.