code: def post_revert_tags(self, post_id, history_id):
          
          params = {'id': post_id, 'history_id': history_id}
          return self._get('post/revert_tags', params, 'PUT')
docs: Function to reverts a post to a previous set of tags
          (Requires login) (UNTESTED).
  
          Parameters:
              post_id (int): The post id number to update.
              history_id (int): The id number of the tag history.