code: func NewKVGetQuery(s string) (*KVGetQuery, error) {
  	if s != "" && !KVGetQueryRe.MatchString(s) {
  		return nil, fmt.Errorf("kv.get: invalid format: %q", s)
  	}
  
  	m := regexpMatch(KVGetQueryRe, s)
  	return &KVGetQuery{
  		stopCh: make(chan struct{}, 1),
  		dc:     m["dc"],
  		key:    m["key"],
  	}, nil
  }
docs: // NewKVGetQuery parses a string into a dependency.