- `spec.usages` is now required, may not contain duplicate values, and must only contain known usages
  - `status.conditions` may not contain duplicate types
  - `status.conditions[*].status` is now required

        assert len(w) >= 2
        duplicate_warnings = [
            warning for warning in w if issubclass(warning.category, UserWarning)
        ]
        assert len(duplicate_warnings) > 0

    int getHash();

    /** Gets the key for this entry. */
    K getKey();

    /** Gets the value for the entry. */
    V getValue();
  }

  /*
   * Note: the following classes have a lot of duplicate code. It sucks, but it saves a lot of
   * memory. If only Java had mixins!
   */

  /** Base class for {@link InternalEntry} implementations for strong keys. */

			}
			if oi.DeleteMarker && (validReplStatus || replicate) {
				dsc.Set(newReplicateTargetDecision(tgtArn, replicate, sync))
				continue
			}
			// can be the case that other cluster is down and duplicate `mc rm --vid`
			// is issued - this still needs to be replicated back to the other target
			if !oi.VersionPurgeStatus.Empty() {

- Fixed an EndpointSlice Controller hashing bug that could cause EndpointSlices to incorrectly handle Pods with duplicate IP addresses. For example this could happen when a new Pod reused an IP that was also assigned to a Pod in a completed state. ([#115907](https://github.com/kubernetes/kubernetes/pull/115907), [@qinqon](https://github.com/qinqon)) [SIG Apps and Network]...

### SIG Storage

- The AllowedTopologies field inside StorageClass is now validated against set and map semantics. Specifically, there cannot be duplicate TopologySelectorTerms, MatchLabelExpressions keys, or TopologySelectorLabelRequirement Values. ([#66843](https://github.com/kubernetes/kubernetes/pull/66843), [@verult](https://github.com/verult))

- EndpointSlice controllers are less likely to create duplicate EndpointSlices. ([#100103](https://github.com/kubernetes/kubernetes/pull/100103), [@robscott](https://github.com/robscott)) [SIG Apps and Network]

            assertArrayEquals(hashAlgos, decodedContext.getHashAlgos());
            assertArrayEquals(salt, decodedContext.getSalt());
        }

        @Test
        @DisplayName("Should handle duplicate hash algorithms")
        void testDuplicateHashAlgos() throws SMBProtocolDecodingException {
            int[] hashAlgos =

* cluster-autoscaler: Fix duplicate writing of logs. ([#45017](https://github.com/kubernetes/kubernetes/pull/45017), [@MaciekPytel](https://github.com/MaciekPytel))

- Improvements were made to `kubeadm reset` related to cleaning  etcd and notifying the user about the state of iptables.
- kubeadm commands now print warnings if input YAML documents contain unknown or duplicate fields.
- kubeadm now properly recognizes Docker 18.09.0 and newer, but still treats 18.06 as the default supported version.
- kubeadm now automatically sets the `--pod-infra-container-image` flag when starting the kubelet.