code: func NewSummaryProvider(statsProvider Provider) SummaryProvider {
  	kubeletCreationTime := metav1.Now()
  	bootTime, err := util.GetBootTime()
  	if err != nil {
  		// bootTime will be zero if we encounter an error getting the boot time.
  		klog.Warningf("Error getting system boot time.  Node metrics will have an incorrect start time: %v", err)
  	}
  
  	return &summaryProviderImpl{
  		kubeletCreationTime: kubeletCreationTime,
  		systemBootTime:      metav1.NewTime(bootTime),
  		provider:            statsProvider,
  	}
  }
docs: // NewSummaryProvider returns a SummaryProvider using the stats provided by the
  // specified statsProvider.