docs: def unparse(text, entities):
      """
      Performs the reverse operation to .parse(), effectively returning HTML
      given a normal text and its MessageEntity's.
  
      :param text: the text to be reconverted into HTML.
      :param entities: the MessageEntity's applied to the text.
      :return: a HTML representation of the combination of both inputs.
      """
      if not text or not entities:
          return text
  
      text = _add_surrogate(text)
      html = []
      last_offset = 0
      for entity in entities:
          if entity.offset > last_offset:
              html.append(escape(text[last_offset:entity.offset]))
          elif entity.offset < last_offset:
              continue
  
          skip_entity = False
          entity_text = escape(text[entity.offset:entity.offset + entity.length])
          entity_type = type(entity)
  
          if entity_type == MessageEntityBold:
              html.append('<strong>{}</strong>'.format(entity_text))
          elif entity_type == MessageEntityItalic:
              html.append('<em>{}</em>'.format(entity_text))
          elif entity_type == MessageEntityCode:
              html.append('<code>{}</code>'.format(entity_text))
          elif entity_type == MessageEntityPre:
              if entity.language:
                  html.append(
                      "<pre>\n"
                      "    <code class='language-{}'>\n"
                      "        {}\n"
                      "    </code>\n"
                      "</pre>".format(entity.language, entity_text))
              else:
                  html.append('<pre><code>{}</code></pre>'
                              .format(entity_text))
          elif entity_type == MessageEntityEmail:
              html.append('<a href="mailto:{0}">{0}</a>'.format(entity_text))
          elif entity_type == MessageEntityUrl:
              html.append('<a href="{0}">{0}</a>'.format(entity_text))
          elif entity_type == MessageEntityTextUrl:
              html.append('<a href="{}">{}</a>'
                          .format(escape(entity.url), entity_text))
          elif entity_type == MessageEntityMentionName:
              html.append('<a href="tg://user?id={}">{}</a>'
                          .format(entity.user_id, entity_text))
          else:
              skip_entity = True
          last_offset = entity.offset + (0 if skip_entity else entity.length)
      html.append(text[last_offset:])
      return _del_surrogate(''.join(html))