code: def parse_recipients(header, reference_id=None):
      
      m = _TO_PATTERN.search(header)
      if not m:
          if reference_id and reference_id not in _CABLES_WITHOUT_TO:
              logger.warn('No TO header found in "%s", header: "%s"' % (reference_id, header))
          return []
      to_header = m.group(1)
      return _route_recipient_from_header(to_header, reference_id)
docs: \
      Returns the recipients of the cable as (maybe empty) list.