leaderelection do not stop leading properly

[ealyn]

What happened (please include outputs or screenshots): After onstarted_leading function throw exception and finish, the process still leading.

What you expected to happen: The process stop leading immediatly.

How to reproduce it (as minimally and precisely as possible): Just follow the leaderelection/example.py.

Anything else we need to know?: Go client use ctx.Done() to find out the OnStartedLeading finish, and then release lock: https://github.com/kubernetes/client-go/blob/1309f64d6648411b4a36a2f7fa84dd8df31884b6/tools/leaderelection/leaderelection.go#L265-L291

Environment:

• Kubernetes version (kubectl version): v1.20.15
• OS (e.g., MacOS 10.13.6): 10.15.7
• Python version (python --version): 3.8.10
• Python client version (pip list | grep kubernetes): 21.7.0

[Manikkame123]

Hi Guys, I am new to this repo. Do you think this issue is good for beginner ?

[roycaihw]

/help

@Manikkame123 Would be great if you could reproduce this issue

[k8s-ci-robot]

@roycaihw: This request has been marked as needing help from a contributor.

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In response to [this](https://github.com/kubernetes-client/python/issues/2075): >/help > >@Manikkame123 Would be great if you could reproduce this issue Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.