1. export Logger lock

logger.go

@@ -315,3 +315,12 @@ func (logger *Logger) level() Level {
 func (logger *Logger) SetLevel(level Level) {
 	atomic.StoreUint32((*uint32)(&logger.Level), uint32(level))
 }
+
+// export mu lock and unlock @bigpigeon
+func (logger *Logger) Lock() {
+	logger.mu.Lock()
+}
+
+func (logger *Logger) Unlock() {
+	logger.mu.Unlock()
+}