code: func (s *ClusterConfigurationService) DeleteStaticTokens() error {
  	err := s.Delete(context.TODO(), backend.Key(clusterConfigPrefix, staticTokensPrefix))
  	if err != nil {
  		if trace.IsNotFound(err) {
  			return trace.NotFound("static tokens are not found")
  		}
  		return trace.Wrap(err)
  	}
  	return nil
  }
docs: // DeleteStaticTokens deletes static tokens