code: func (lr *logRegistry) ListLoggers() map[string]string {
  	list := make(map[string]string)
  
  	var wasErr error
  
  	lr.loggers.Range(func(k, v interface{}) bool {
  		key, ok := k.(string)
  		if !ok {
  			wasErr = fmt.Errorf("cannot cast log map key to string")
  			// false stops the iteration
  			return false
  		}
  		value, ok := v.(*Logger)
  		if !ok {
  			wasErr = fmt.Errorf("cannot cast log value to Logger obj")
  			return false
  		}
  		list[key] = value.GetLevel().String()
  		return true
  	})
  
  	// throw panic outside of logger.Range()
  	if wasErr != nil {
  		panic(wasErr)
  	}
  
  	return list
  }
docs: // ListLoggers returns a map (loggerName => log level)