func InstanceID() (string, error) {
	lock.RLock()
	defer lock.RUnlock()
	if cachedInstanceID != "" {
		return cachedInstanceID, nil
	} else {
		var err error
		cachedInstanceID, err = fetchInstanceID()
		return cachedInstanceID, err
	}
}
// InstanceID returns the current instance id
InstanceID returns the current instance id
// InstanceID returns the current instance id
func InstanceID() (string, error) {
	lock.RLock()
	defer lock.RUnlock()
	if cachedInstanceID != "" {
		return cachedInstanceID, nil
	} else {
		var err error
		cachedInstanceID, err = fetchInstanceID()
		return cachedInstanceID, err
	}
}
func InstanceID ( ) ( string , error ) { lock . RLock ( ) defer lock . RUnlock ( ) if cachedInstanceID != " " { return cachedInstanceID , nil } else { var err error cachedInstanceID , err = fetchInstanceID ( ) return cachedInstanceID , err } }
InstanceID returns the current instance id
InstanceID returns the current instance id