code: def get_cgi_parameter_datetime(form: cgi.FieldStorage,
                                 key: str) -> Optional[datetime.datetime]:
      
      try:
          s = get_cgi_parameter_str(form, key)
          if not s:
              # if you dateutil.parser.parse() an empty string,
              # you get today's date
              return None
          d = dateutil.parser.parse(s)
          if d.tzinfo is None:  # as it will be
              d = d.replace(tzinfo=dateutil.tz.tzlocal())
          return d
      except ValueError:
          return None
docs: Extracts a date/time parameter from a CGI form. Applies the LOCAL
      timezone if none specified.