code: def create(self, items=[], taxes=[], custom_data=[]):
          
          self.add_items(items)
          self.add_taxes(taxes)
          self.add_custom_data(custom_data)
          return self._process('checkout-invoice/create', self._prepare_data)
docs: Adds the items to the invoice
  
          Format of 'items':
          [
           InvoiceItem(
               name="VIP Ticket",
               quantity= 2,
               unit_price= "3500",
               total_price= "7000",
               description= "VIP Tickets for the Party"
            }
          ,...
          ]