code: def validate(self):
          
          try:
              assert self.kind == content_kinds.TOPIC, "Assumption Failed: Node is supposed to be a topic"
              return super(TopicNode, self).validate()
          except AssertionError as ae:
              raise InvalidNodeException("Invalid node ({}): {} - {}".format(ae.args[0], self.title, self.__dict__))
docs: validate: Makes sure topic is valid
              Args: None
              Returns: boolean indicating if topic is valid