code: public OvhConfigurationItem cart_cartId_item_itemId_configuration_POST(String cartId, Long itemId, String label, String value) throws IOException {
  		String qPath = "/order/cart/{cartId}/item/{itemId}/configuration";
  		StringBuilder sb = path(qPath, cartId, itemId);
  		HashMap<String, Object>o = new HashMap<String, Object>();
  		addBody(o, "label", label);
  		addBody(o, "value", value);
  		String resp = execN(qPath, "POST", sb.toString(), o);
  		return convertTo(resp, OvhConfigurationItem.class);
  	}
docs: Setup configuration item for the product
  
  REST: POST /order/cart/{cartId}/item/{itemId}/configuration
  @param cartId [required] Cart identifier
  @param itemId [required] Product item identifier
  @param label [required] Label for your configuration item
  @param value [required] Value or resource URL on API.OVH.COM of your configuration item