code: def get_cfws(value):
      
      cfws = CFWSList()
      while value and value[0] in CFWS_LEADER:
          if value[0] in WSP:
              token, value = get_fws(value)
          else:
              token, value = get_comment(value)
          cfws.append(token)
      return cfws, value
docs: CFWS = (1*([FWS] comment) [FWS]) / FWS