code: def append_attribute(self, name, value, content):
          
          type = self.resolver.findattr(name)
          if type is None:
              log.warn('attribute (%s) type, not-found', name)
          else:
              value = self.translated(value, type)
          Core.append_attribute(self, name, value, content)
docs: Append an attribute name/value into L{Content.data}.
          @param name: The attribute name
          @type name: basestring
          @param value: The attribute's value
          @type value: basestring
          @param content: The current content being unmarshalled.
          @type content: L{Content}