old_contents: # encoding=utf8
  from lxml import html
  
  
  def _recursive_convert(element):
      # All strings outside tags should be ignored
      if not isinstance(element, html.HtmlElement):
          return
  
      fragment_root_element = {
          '_': element.tag
      }
  
      content = []
      if element.text:
          content.append({'t': element.text})
  
      if element.attrib:
          fragment_root_element.update({
              'a': dict(element.attrib)
          })
  
      for child in element:
          content.append(_recursive_convert(child))
          # Append Text node after element, if exists
          if child.tail:
              content.append({'t': child.tail})
  
      if len(content):
          fragment_root_element.update({
              'c': content
          })
  
      return fragment_root_element
  
  
  def convert_html_to_telegraph_format(html_string):
      return [
          _recursive_convert(fragment) for fragment in html.fragments_fromstring(html_string)
      ]
  
new_contents: # encoding=utf8
  from lxml import html
  import json
  
  
  def _recursive_convert(element):
      # All strings outside tags should be ignored
  
      fragment_root_element = {
          '_': element.tag
      }
  
      content = []
      if element.text:
          content.append({'t': element.text})
  
      if element.attrib:
          fragment_root_element.update({
              'a': dict(element.attrib)
          })
  
      for child in element:
          content.append(_recursive_convert(child))
          # Append Text node after element, if exists
          if child.tail:
              content.append({'t': child.tail})
  
      if len(content):
          fragment_root_element.update({
              'c': content
          })
  
      return fragment_root_element
  
  
  def convert_html_to_telegraph_format(html_string):
      content = []
      for fragment in html.fragments_fromstring(html_string):
          if not isinstance(fragment, html.HtmlElement):
              continue
  
          content.append(_recursive_convert(fragment))
      return json.dumps(content, ensure_ascii=False)
  
subject: Return string instead of list