You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: node_tree.go
    path of file: ./repos/kubernetes/pkg/scheduler/internal/cache
    
    the code of the file until where you have to start completion: /*
Copyright 2018 The Kubernetes Authors.

Licensed under the Apache Lic
    
func (nt *nodeTree) updateNode(logger klog.Logger, old, new *v1.Node) {
	var oldZone string
	if old != nil {
		oldZone = utilnode.GetZoneKey(old)
	}
	newZone := utilnode.GetZoneKey(new)
	// If the zone ID of the node has not changed, we don't need to do anything. Name of the node
	// cannot be changed in an update.
	if oldZone == newZone {
		return
	}
	nt.removeNode(logger, old) // No error checking. We ignore whether the old node exists or not.
	nt.addNode(logger, new)
}