code: def append(self):
          
          tag = self._schema.tag
          children = self._root.getchildren()
          if len(children) >= self._schema.max_occurs:
              raise WSDLParseError("Too many items in tag '%s'" % tag)
          schema = self._schema.child
          tag = "item"
          if self._namespace is not None:
              tag = "{%s}%s" % (self._namespace, tag)
          child = etree.SubElement(self._root, tag)
          return schema.create(child)
docs: Append a new item to the sequence, appending it to the end.
  
          @return: The newly created item.
          @raises L{WSDLParseError}: If the operation would result in having
               more child elements than the allowed max.