#### CLI Changes

- [alpha] `kubectl` plugins: `kubectl` now allows binary extensibility. You can extend the default set of `kubectl` commands by writing plugins
  that provide new subcommands. Refer to the documentation for more information.

- `kubectl rollout` and `rollback` now support StatefulSet.

[Special Interest Groups](https://github.com/kubernetes/community/blob/master/sig-list.md), which provide the themes that guide their work. For the 1.9 release, these themes included:

### API Machinery

Extensibility. SIG API Machinery added a new class of admission control webhooks (mutating), and brought the admission control webhooks to beta.

### Apps

- **Admission webhooks:** Admission webhooks are in widespread use as a Kubernetes extensibility mechanism and have been available in beta since the 1.9 release. The 1.16 release marks the graduation of admission webhooks to general availability (GA).

* Improved **correctness** in corner cases.
* **Safer** types.
* Better **performance** and **less energy** consumption.
* Better **extensibility**.
* etc.

...all this while keeping the **same Python API**. In most of the cases, for simple models, you can simply upgrade the Pydantic version and get all the benefits. 🚀