code: func (ar AliasesResult) IndicesByAlias(aliasName string) []string {
  	var indices []string
  	for indexName, indexInfo := range ar.Indices {
  		for _, aliasInfo := range indexInfo.Aliases {
  			if aliasInfo.AliasName == aliasName {
  				indices = append(indices, indexName)
  			}
  		}
  	}
  	return indices
  }
docs: // IndicesByAlias returns all indices given a specific alias name.