code: func (s *Store) aclTokenGet(ws memdb.WatchSet, value, index string) (uint64, *structs.ACLToken, error) {
  	tx := s.db.Txn(false)
  	defer tx.Abort()
  
  	token, err := s.aclTokenGetTxn(tx, ws, value, index)
  	if err != nil {
  		return 0, nil, fmt.Errorf("failed acl token lookup: %v", err)
  	}
  
  	idx := maxIndexTxn(tx, "acl-tokens")
  	return idx, token, nil
  }
docs: // aclTokenGet looks up a token using one of the indexes provided