}

  /**
   * Returns the specified comparator if not null; otherwise returns {@code Ordering.natural()}.
   * This method is an abomination of generics; the only purpose of this method is to contain the
   * ugly type-casting in one place.
   */
  @SuppressWarnings("unchecked")
  static <E extends @Nullable Object> Comparator<? super E> orNaturalOrder(
      @Nullable Comparator<? super E> comparator) {

- The AWS credential provider can now obtain ECR credentials even without the AWS cloud provider or being on an EC2 instance. Additionally, AWS credential provider caching has been improved to honor the ECR credential timeout. ([#75587](https://github.com/kubernetes/kubernetes/pull/75587), [@tiffanyfay](https://github.com/tiffanyfay))


### Azure

* Use inline func to ensure unlock is executed ([#61644](https://github.com/kubernetes/kubernetes/pull/61644), [@resouer](https://github.com/resouer))

### Federation
* **[beta]** `kubefed` has graduated to beta: supports hosting federation on on-prem clusters, automatically configures `kube-dns` in joining clusters and allows passing arguments to federation components.

### Internal Storage Layer

- Kube-apiserver: the alpha PodSecurity feature can be enabled by passing `--feature-gates=PodSecurity=true`, and enables controlling allowed pods using namespace labels. See https://git.k8s.io/enhancements/keps/sig-auth/2579-psp-replacement for more details. ([#103099](https://github.com/kubernetes/kubernetes/pull/103099),...

### SIG Network

For 1.13, the areas of focus were in IPv6, DNS improvements and some smaller items:
CoreDNS is now the default cluster DNS passing all of the scale/resource usage tests
Node-local DNS cache feature is available in Alpha. This feature deploys a lightweight DNS caching Daemonset that avoids the conntrack and converts queries from UDP to more reliable TCP.
PodReady++ feature now has `kubectl` CLI support.