code: def transform_content(tags, content_transformer):
      
      if type(tags) not in [tuple, list]:
          tags = [tags]
  
      for tag in tags:
          new_child = dhtmlparser.HTMLElement(content_transformer(tag))
  
          # don't forget to add parent if the list is double-linked
          if hasattr(tag, "parent"):
              new_child.parent = tag
  
          tag.childs = [new_child]
docs: Transform content in all `tags` using result of `content_transformer(tag)`
      call.
  
      Args:
          tags (obj/list): HTMLElement instance, or list of HTMLElement
                           instances.
          content_transformer (function): Function which is called as
                                          ``content_transformer(tag)``.