分析Kubernetes中的领导者选举(leaderelection.go)

I am studying about leader election in Kubernetes. I know that K8S provide a leader election leaderelection.go

I read in some papers, they said that this leader election leverage Etcd (that already built in K8S and use Raft consensus).

But when I read the code in leaderlection.go, I did not see any relationship here!

Can someone help me to point out the piece code which talk with Etcd (to use Raft for leader election)

Actually, I want to debug this code to study leader election. Can you teach me the way how to analyze these code in K8S?