code: def error_message(self):
      
      if 'error' in self._op:
        if 'task-id' in self._op['metadata']['labels']:
          job_id = self._op['metadata']['labels']['task-id']
        else:
          job_id = self._op['metadata']['labels']['job-id']
        return 'Error in job %s - code %s: %s' % (job_id,
                                                  self._op['error']['code'],
                                                  self._op['error']['message'])
      else:
        return ''
docs: Returns an error message if the operation failed for any reason.
  
      Failure as defined here means; ended for any reason other than 'success'.
      This means that a successful cancelation will also create an error message
      here.
  
      Returns:
        string, string will be empty if job did not error.