code: func NewIndicesStatsService(client *Client) *IndicesStatsService {
  	return &IndicesStatsService{
  		client:           client,
  		index:            make([]string, 0),
  		metric:           make([]string, 0),
  		completionFields: make([]string, 0),
  		fielddataFields:  make([]string, 0),
  		fields:           make([]string, 0),
  		groups:           make([]string, 0),
  		types:            make([]string, 0),
  	}
  }
docs: // NewIndicesStatsService creates a new IndicesStatsService.