code: public CoinbaseOrder createCoinbaseOrder(String code) throws IOException {
  
      final CoinbaseOrder createdOrder =
          coinbase.createOrder(
              code,
              exchange.getExchangeSpecification().getApiKey(),
              signatureCreator,
              exchange.getNonceFactory());
      return handleResponse(createdOrder);
    }
docs: Authenticated resource which lets you generate an order associated with a button. After
  generating an order, you can send Bitcoin to the address associated with the order to complete
  the order. The status of this newly created order will be ‘new’.
  
  @param code The code of the button for which you wish to create an order.
  @return The newly created {@code CoinbaseOrder}.
  @throws IOException
  @see <a
  href="https://coinbase.com/api/doc/1.0/buttons/create_order.html">coinbase.com/api/doc/1.0/buttons/create_order.html</a>