code: def discover(self, transaction):
          
          transaction.response.code = defines.Codes.CONTENT.number
          payload = ""
          for i in self._parent.root.dump():
              if i == "/":
                  continue
              resource = self._parent.root[i]
              if resource.visible:
                  ret = self.valid(transaction.request.uri_query, resource.attributes)
                  if ret:
                      payload += self.corelinkformat(resource)
  
          transaction.response.payload = payload
          transaction.response.content_type = defines.Content_types["application/link-format"]
          return transaction
docs: Render a GET request to the .well-know/core link.
  
          :param transaction: the transaction
          :return: the transaction