the corresponding iteration value will not be produced. If a map entry is
created during iteration, that entry may be produced during the iteration or
may be skipped. The choice may vary for each entry created and from one
iteration to the next.
If the map is <code>nil</code>, the number of iterations is 0.
</li>

<li>
For channels, the iteration values produced are the successive values sent on

* Clarify function name in example in docs. PR [#1121](https://github.com/tiangolo/fastapi/pull/1121) by [@tmsick](https://github.com/tmsick).
* Add external link [Apache Kafka producer and consumer with FastAPI and aiokafka](https://iwpnd.pw/articles/2020-03/apache-kafka-fastapi-geostream) to docs. PR [#1112](https://github.com/tiangolo/fastapi/pull/1112) by [@iwpnd](https://github.com/iwpnd).

  // cannot be resolved, the reference in the input string will be unchanged. Double $$ are reduced
  // to a single $, which allows for escaping the $(VAR_NAME) syntax: i.e. "$$(VAR_NAME)" will
  // produce the string literal "$(VAR_NAME)". Escaped references will never be expanded, regardless
  // of whether the variable exists or not. Cannot be updated.

* kubeadm now produces error during preflight checks if swap is enabled. Users, who can setup kubelet to run in unsupported environment with enabled swap, will be able to skip that preflight check. ([#55399](https://github.com/kubernetes/kubernetes/pull/55399), [@kad](https://github.com/kad))

- Fixes a goroutine leak in kube-apiserver when a request times out. ([#83333](https://github.com/kubernetes/kubernetes/pull/83333), [@lavalamp](https://github.com/lavalamp))
- Fixes the bug in informer-gen that it produces incorrect code if a type has nonNamespaced tag set. ([#80458](https://github.com/kubernetes/kubernetes/pull/80458), [@tatsuhiro-t](https://github.com/tatsuhiro-t))

* Flex drivers by default do not produce metrics. Flex plugins can enable metrics collection by setting  the capability 'supportsMetrics' to true. Make sure the file system can support fs stat to produce metrics in this case. ([#67508](https://github.com/kubernetes/kubernetes/pull/67508), [@brahmaroutu](https://github.com/brahmaroutu))

- Graduated the `LegacyServiceAccountTokenTracking` feature gate to GA. The usage of auto-generated secret-based service account token now produces warnings, and relevant Secrets are labeled with a last-used timestamp (label key `kubernetes.io/legacy-token-last-used`). ([#117591](https://github.com/kubernetes/kubernetes/pull/117591), [@zshihang](https://github.com/zshihang)) [SIG API Machinery,...

Due to a [tagging bug in our Release Engineering tooling](https://github.com/kubernetes/release/issues/1080) during `v1.18.0-alpha.3`, we needed to push a manual tag (`v1.18.0-alpha.4`).

**No binaries have been produced or will be provided for `v1.18.0-alpha.4`.**

The changelog for `v1.18.0-alpha.4` is included as part of the [changelog since v1.18.0-alpha.3][#changelog-since-v1180-alpha3] section.

# v1.18.0-alpha.3

 - Pods that are considered for preemption and haven't started don't produce an error log. ([#90241](https://github.com/kubernetes/kubernetes/pull/90241), [@alculquicondor](https://github.com/alculquicondor)) [SIG Scheduling]

  can also be scheduled to nodes with `GA` labels. ([#118923](https://github.com/kubernetes/kubernetes/pull/118923), [@AxeZhan](https://github.com/AxeZhan))
- Updated the generic apiserver library to produce an error if a new API server is configured with support for a data format other than JSON, YAML, or Protobuf. ([#121325](https://github.com/kubernetes/kubernetes/pull/121325), [@benluddy](https://github.com/benluddy)) [SIG API Machinery]