code: def upload(self):
      
      if not self._converter:
        raise RuntimeError(
            'Must set _converter on subclass or via set_converter before calling '
            'upload.')
  
      if not self.credentials:
        raise RuntimeError('Must provide credentials to use upload callback.')
  
      def upload_callback(test_record_obj):
        proto = self._convert(test_record_obj)
        self.upload_result = send_mfg_inspector_data(
            proto, self.credentials, self.destination_url)
  
      return upload_callback
docs: Returns a callback to convert a test record to a proto and upload.