code: def complete_xml_element(self, xmlnode, _unused):
          
          tm=self.timestamp.strftime("%Y%m%dT%H:%M:%S")
          xmlnode.setProp("stamp",tm)
          if self.delay_from:
              xmlnode.setProp("from",self.delay_from.as_utf8())
          if self.reason:
              xmlnode.setContent(to_utf8(self.reason))
docs: Complete the XML node with `self` content.
  
          Should be overriden in classes derived from `StanzaPayloadObject`.
  
          :Parameters:
              - `xmlnode`: XML node with the element being built. It has already
                right name and namespace, but no attributes or content.
              - `_unused`: document to which the element belongs.
          :Types:
              - `xmlnode`: `libxml2.xmlNode`
              - `_unused`: `libxml2.xmlDoc`