code: def _parse_ISBN_EAN(details):
      
      isbn_ean = _get_td_or_none(
          details,
          "ctl00_ContentPlaceHolder1_tblRowIsbnEan"
      )
  
      if not isbn_ean:
          return None, None
  
      ean = None
      isbn = None
      if "/" in isbn_ean:  # ISBN and EAN are stored in same string
          isbn, ean = isbn_ean.split("/")
          isbn = isbn.strip()
          ean = ean.strip()
      else:
          isbn = isbn_ean.strip()
  
      if not isbn:
          isbn = None
  
      return isbn, ean
docs: Parse ISBN and EAN.
  
      Args:
          details (obj): HTMLElement containing slice of the page with details.
  
      Returns:
          (ISBN, EAN): Tuple with two string or two None.