func setLog(l *log.Logger) {
	if l != nil {
		logger = l
	} else {
		logger = log.New(ioutil.Discard, "", 0)
	}
}
func setLog(l *log.Logger) {
	if l != nil {
		logger = l
	} else {
		logger = log.New(ioutil.Discard, "", 0)
	}
}
func setLog ( l * log . Logger ) { if l != nil { logger = l } else { logger = log . New ( ioutil . Discard , " " , 0 ) } }
// setLog sets the logger.
setLog sets the logger .