func IsExist(err error) bool {
	if err == ErrUserExist || err == ErrGroupExist {
		return true
	}
	return false
}
func IsExist(err error) bool {
	if err == ErrUserExist || err == ErrGroupExist {
		return true
	}
	return false
}
func IsExist ( err error ) bool { if err == ErrUserExist || err == ErrGroupExist { return true } return false }
// IsExist returns whether the error is known to report that an user or group
// already exists. It is satisfied by ErrUserExist and ErrGroupExist.
IsExist returns whether the error is known to report that an user or group already exists . It is satisfied by ErrUserExist and ErrGroupExist .