"optional": "optional specify whether the ConfigMap or its keys...

  // key and content is the value. If specified, the listed keys will be
  // projected into the specified paths, and unlisted keys will not be
  // present. If a key is specified which is not present in the ConfigMap,
  // the volume setup will error unless it is marked optional. Paths must be
  // relative and may not contain the '..' path or start with '..'.
  // +optional

				Description: "UpdateOptions may be provided when updating an API object. All fields in UpdateOptions should also be present in PatchOptions.",
				Type:        []string{"object"},
				Properties: map[string]spec.Schema{
					"kind": {
						SchemaProps: spec.SchemaProps{

	// PullNever means that kubelet never pulls an image, but only uses a local image. Container will fail if the image isn't present
	PullNever PullPolicy = "Never"
	// PullIfNotPresent means that kubelet pulls if the image isn't present on disk. Container will fail if the image isn't present and the pull fails.
	PullIfNotPresent PullPolicy = "IfNotPresent"
)

  // key and content is the value. If specified, the listed keys will be
  // projected into the specified paths, and unlisted keys will not be
  // present. If a key is specified which is not present in the ConfigMap,
  // the volume setup will error unless it is marked optional. Paths must be
  // relative and may not contain the '..' path or start with '..'.
  // +optional
  // +listType=atomic

ParameterList  = ParameterDecl { "," ParameterDecl } .
ParameterDecl  = [ IdentifierList ] [ "..." ] Type .
</pre>

<p>
Within a list of parameters or results, the names (IdentifierList)
must either all be present or all be absent. If present, each name
stands for one item (parameter or result) of the specified type and
all non-<a href="#Blank_identifier">blank</a> names in the signature
must be <a href="#Uniqueness_of_identifiers">unique</a>.

	abiSelf := abiForFunc(fn, ssaConfig.ABI0, ssaConfig.ABI1)

	printssa := false
	// match either a simple name e.g. "(*Reader).Reset", package.name e.g. "compress/gzip.(*Reader).Reset", or subpackage name "gzip.(*Reader).Reset"
	// optionally allows an ABI suffix specification in the GOSSAHASH, e.g. "(*Reader).Reset<0>" etc
	if strings.Contains(ssaDump, name) { // in all the cases the function name is entirely contained within the GOSSAFUNC string.

- kubeadm reset: unmount directories under `/var/lib/kubelet` for Linux only ([#81494](https://github.com/kubernetes/kubernetes/pull/81494), [@Klaven](https://github.com/Klaven))
- kubeadm: fix the bug that `--cri-socket` flag does not work for `kubeadm reset` ([#79498](https://github.com/kubernetes/kubernetes/pull/79498), [@SataQiu](https://github.com/SataQiu))

* kubectl apply now supports explicitly clearing values not present in the config by setting them to null ([#40630](https://github.com/kubernetes/kubernetes/pull/40630), [@liggitt](https://github.com/liggitt))

* Fixed a bug which could prevent a provider ID from ever being set for node if an error occurred determining the provider ID when the node was added. ([#87043](https://github.com/kubernetes/kubernetes/pull/87043), [@zjs](https://github.com/zjs))