log_adapter.go
func (la *LogAdapter) Debugf(msg string, a ...interface{}) error {
	return la.Log(LevelDebug, nil, msg, a...)
}
func (la *LogAdapter) Debugf(msg string, a ...interface{}) error {
	return la.Log(LevelDebug, nil, msg, a...)
}
/*
Debugf uses msg as a format string with subsequent parameters as values and logs
the resulting message to all added loggers at LogLevel.LevelDebug
*/