code: func (s *ScrollService) Slice(sliceQuery Query) *ScrollService {
  	s.ss = s.ss.Slice(sliceQuery)
  	return s
  }
docs: // Slice allows slicing the scroll request into several batches.
  // This is supported in Elasticsearch 5.0 or later.
  // See https://www.elastic.co/guide/en/elasticsearch/reference/7.0/search-request-scroll.html#sliced-scroll
  // for details.