// Time when this Event was first observed.
  // +optional
  optional k8s.io.apimachinery.pkg.apis.meta.v1.MicroTime eventTime = 10;

  // Data about the Event series this event represents or nil if it's a singleton Event.
  // +optional
  optional EventSeries series = 11;

  // What action was taken/failed regarding to the Regarding object.
  // +optional
  optional string action = 12;

- Changed kubectl `--subresource` flag to beta ([#116595](https://github.com/kubernetes/kubernetes/pull/116595), [@MadhavJivrajani](https://github.com/MadhavJivrajani))
- Changed metrics for aggregated discovery to publish new time series (alpha). ([#115630](https://github.com/kubernetes/kubernetes/pull/115630), [@Jefftree](https://github.com/Jefftree)) [SIG API Machinery and Testing]

### Generic Ephemeral Volumes

- Added a kubelet socket which serves an grpc service containing the devices used by containers on the node. ([#70508](https://github.com/kubernetes/kubernetes/pull/70508), [@dashpole](https://github.com/dashpole))

  * Allow configuration of a single security group for ELBs ([#45500](https://github.com/kubernetes/kubernetes/pull/45500), [@nbutton23](https://github.com/nbutton23))

  * Remove check that forces loadBalancerSourceRanges to be 0.0.0.0/0. ([#38636](https://github.com/kubernetes/kubernetes/pull/38636), [@dhawal55](https://github.com/dhawal55))

the body of any nested function.
</p>


<h3 id="Blank_identifier">Blank identifier</h3>

<p>
The <i>blank identifier</i> is represented by the underscore character <code>_</code>.
It serves as an anonymous placeholder instead of a regular (non-blank)
identifier and has special meaning in <a href="#Declarations_and_scope">declarations</a>,

  the garbage collector starts to manage it.


#### Monitoring/Prometheus
* [action required] The WATCHLIST calls are now reported as WATCH verbs in prometheus for the apiserver_request_* series.  A new "scope" label is added to all apiserver_request_* values that is either 'cluster', 'resource', or 'namespace' depending on which level the query is performed at.([#52237](https://github.com/kubernetes/kubernetes/pull/52237))

  - The `export` query parameter for list API calls, deprecated since v1.14, will be removed in v1.18.
  - The `series.state` field in the events.k8s.io/v1beta1 Event API is deprecated and will be removed in v1.18 ([#75987](https://github.com/kubernetes/kubernetes/pull/75987), [@yastij](https://github.com/yastij))

- kubeadm

- 'kubeadm: marked the flag "--experimental-output'' as deprecated (it will
  be removed in a future release) and added a new flag ''--output" that serves the
  same purpose. Affected commands are - "kubeadm config images list", "kubeadm token

* Splits Juju Charm layers into master/worker roles ([#40324](https://github.com/kubernetes/kubernetes/pull/40324), [@chuckbutler](https://github.com/chuckbutler))
    * Adds support for 1.5.x series of Kubernetes
    * Introduces a tactic for keeping templates in sync with upstream eliminating template drift
    * Adds CNI support to the Juju Charms
    * Adds durable storage support to the Juju Charms