code: func (c Client) CreateOrderFromButtonCode(buttonCode string) (*order, error) {
  	holder := orderHolder{}
  	if err := c.Post("buttons/"+buttonCode+"/create_order", nil, &holder); err != nil {
  		return nil, err
  	}
  	if err := checkApiErrors(holder.response, "CreateOrderFromButtonCode"); err != nil {
  		return nil, err
  	}
  	return &holder.Order, nil
  }
docs: // CreateOrderFromButtonCode creates an order for a given button code