code: func (s SecureJsonData) DecryptedValue(key string) (string, bool) {
  	if value, ok := s[key]; ok {
  		decryptedData, err := util.Decrypt(value, setting.SecretKey)
  		if err != nil {
  			log.Fatal(4, err.Error())
  		}
  		return string(decryptedData), true
  	}
  	return "", false
  }
docs: // DecryptedValue returns single decrypted value from SecureJsonData. Similar to normal map access second return value
  // is true if the key exists and false if not.