code: func (ca *cloudCIDRAllocator) AllocateOrOccupyCIDR(node *v1.Node) error {
  	if node == nil {
  		return nil
  	}
  	if !ca.insertNodeToProcessing(node.Name) {
  		klog.V(2).Infof("Node %v is already in a process of CIDR assignment.", node.Name)
  		return nil
  	}
  
  	klog.V(4).Infof("Putting node %s into the work queue", node.Name)
  	ca.nodeUpdateChannel <- node.Name
  	return nil
  }
docs: // WARNING: If you're adding any return calls or defer any more work from this
  // function you have to make sure to update nodesInProcessing properly with the
  // disposition of the node when the work is done.