code: def documents(self):
          
          if self._documents is None:
              self._documents = DocumentList(self._version, service_sid=self._solution['sid'], )
          return self._documents
docs: Access the documents
  
          :returns: twilio.rest.sync.v1.service.document.DocumentList
          :rtype: twilio.rest.sync.v1.service.document.DocumentList