code: func (d *DaemonSetPrepuller) WaitFunc(component string) {
  	fmt.Printf("[upgrade/prepull] Prepulling image for component %s.\n", component)
  	d.waiter.WaitForPodsWithLabel("k8s-app=upgrade-prepull-" + component)
  }
docs: // WaitFunc waits for all Pods in the specified DaemonSet to be in the Running state