#### What type of PR is this?

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/kind bug
/kind cleanup
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/kind feature

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/kind api-change
/kind deprecation
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#### What this PR does / why we need it:

#### Which issue(s) this PR fixes:
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<img src="/img/tutorial/extending-openapi/image03.png">

## Change the Theme

The same way you could set the syntax highlighting theme with the key `"syntaxHighlight.theme"` (notice that it has a dot in the middle):

```Python hl_lines="3"
{!../../../docs_src/configure_swagger_ui/tutorial002.py!}
```

That configuration would change the syntax highlighting color theme:

sure your code compiles by running `./gradlew check`. Checkstyle failures
during compilation indicate errors in your style and can be viewed in the
`checkstyle-result.xml` file.

Some general advice

- Don’t change public API lightly, avoid if possible, and include your reasoning in the PR if essential.  It causes pain for developers who use OkHttp and sometimes runtime errors.

_2019-06-21_

 *  New: Require Kotlin 1.3.40.
 *  New: Change the Kotlin API from `File.toRequestBody()` to `File.asRequestBody()` and
    `BufferedSource.toResponseBody()` to `BufferedSource.asResponseBody()`. If the returned value
    is a view of what created it, we use _as_.
 *  Fix: Permit response codes of zero for compatibility with OkHttp 3.x.
 *  Fix: Change the return type of `MockWebServer.takeRequest()` to be nullable.

    - [Container Images](#container-images-1)
  - [Changelog since v1.23.15](#changelog-since-v12315)
  - [Changes by Kind](#changes-by-kind-1)
    - [API Change](#api-change)
    - [Feature](#feature-1)
    - [Bug or Regression](#bug-or-regression-1)
  - [Dependencies](#dependencies-1)
    - [Added](#added-1)
    - [Changed](#changed-1)
    - [Removed](#removed-1)
- [v1.23.15](#v12315)
  - [Downloads for v1.23.15](#downloads-for-v12315)

the Gerrit change.

**Please ensure you adhere to every item in this list.**

More info can be found at https://github.com/golang/go/wiki/CommitMessage

+ The PR title is formatted as follows: `net/http: frob the quux before blarfing`
  + The package name goes before the colon
  + The part after the colon uses the verb tense + phrase that completes the blank in,
    "This change modifies Go to ___________"

                    dir(isUnix() ? 'test' : "c:\\mvn-it-${EXECUTOR_NUMBER}.tmp") {
                        def WORK_DIR=pwd()
                        def ITS_BRANCH = env.CHANGE_BRANCH != null ? env.CHANGE_BRANCH :  env.BRANCH_NAME;
                        try {
                          echo "Checkout ITs from branch: ${ITS_BRANCH}"
                          checkout([$class: 'GitSCM',

  - [Changelog since v1.20.11](#changelog-since-v12011)
  - [Changes by Kind](#changes-by-kind-3)
    - [API Change](#api-change)
    - [Bug or Regression](#bug-or-regression-3)
    - [Other (Cleanup or Flake)](#other-cleanup-or-flake)
  - [Dependencies](#dependencies-3)
    - [Added](#added-3)
    - [Changed](#changed-3)
    - [Removed](#removed-3)
- [v1.20.11](#v12011)

    - [Node Binaries](#node-binaries-5)
  - [Changelog since v1.19.10](#changelog-since-v11910)
  - [Changes by Kind](#changes-by-kind-5)
    - [API Change](#api-change)
    - [Feature](#feature-3)
    - [Bug or Regression](#bug-or-regression-4)
  - [Dependencies](#dependencies-5)
    - [Added](#added-5)
    - [Changed](#changed-5)
    - [Removed](#removed-5)
- [v1.19.10](#v11910)
  - [Downloads for v1.19.10](#downloads-for-v11910)