docs: def _parse_publisher(details):
      """
      Parse publisher of the book.
  
      Args:
          details (obj): HTMLElement containing slice of the page with details.
  
      Returns:
          str/None: Publisher's name as string or None if not found.
      """
      publisher = _get_td_or_none(
          details,
          "ctl00_ContentPlaceHolder1_tblRowNakladatel"
      )
  
      # publisher is not specified
      if not publisher:
          return None
  
      publisher = dhtmlparser.removeTags(publisher).strip()
  
      # return None instead of blank string
      if not publisher:
          return None
  
      return publisher