You can limit the lines used from the docstring of a *path operation function* for OpenAPI.

Adding an `\f` (an escaped "form feed" character) causes **FastAPI** to truncate the output used for OpenAPI at this point.

It won't show up in the documentation, but other tools (such as Sphinx) will be able to use the rest.

```Python hl_lines="19-29"
{!../../../docs_src/path_operation_advanced_configuration/tutorial004.py!}
```

    }.flatMap { it.functionalTests }.filter { it.os == os }

    if (os == Os.LINUX) {
        steps {
            script {
                // Because we exclude tests in `distributions-integ-tests` below, `@Flaky` won't work in that subproject.
                // Here we check the existence of `@Flaky` annotation to make sure nobody use that annotation in `distributions-integ-tests` subproject.

    /*
     * We use `fromNullable` instead of `of` because `WeakReference.get()` has a nullable return
     * type.
     *
     * In practice, we are very unlikely to see `null`: The `WeakReference` to the enum constant
     * won't be cleared as long as the enum constant is referenced somewhere, and the enum constant
     * is referenced somewhere for as long as the enum class is loaded. *Maybe in theory* the enum

 * connections should expect repetition of stream IDs.
 *
 * Return true to request cancellation of a pushed stream.  Note that this does not guarantee
 * future frames won't arrive on the stream ID.
 */
interface PushObserver {
  /**
   * Describes the request that the server intends to push a response for.
   *
   * @param streamId server-initiated stream ID: an even number.

    assertThat(statusLine.protocol).isEqualTo(Protocol.HTTP_1_1)
    assertThat(statusLine.code).isEqualTo(code)
  }

  /**
   * This is not defined in the protocol but some servers won't add the leading empty space when the
   * message is empty. http://www.w3.org/Protocols/rfc2616/rfc2616-sec6.html#sec6.1
   */
  @Test
  fun emptyMessageAndNoLeadingSpace() {
    val version = 1
    val code = 503

      - name: 'Test'
        shell: bash
        run: ./mvnw -B -P!standard-with-extra-repos verify -U -Dmaven.javadoc.skip=true -f $ROOT_POM
      - name: 'Print Surefire reports'
        # Note: Normally a step won't run if the job has failed, but this causes it to
        if: ${{ failure() }}
        shell: bash
        run: ./util/print_surefire_reports.sh
      - name: 'Integration Test'
        if: matrix.java == 11

        ? SortedSetTestSuiteBuilder.using((TestSortedSetGenerator<K>) keySetGenerator)
        : SetTestSuiteBuilder.using(keySetGenerator);
  }

  /**
   * To avoid infinite recursion, test suites with these marker features won't have derived suites
   * created for them.
   */
  enum NoRecurse implements Feature<@Nullable Void> {
    SUBMAP,
    DESCENDING;

    @Override

includes_test_changes: {{ files | match(regex=r/.*\/(test|integTest|crossVersionTest|docsTest|smokeTest)\//) | some }}
is_docs_only_change: {{ (files | allDocs) or (files | match(regex=r/\.adoc$/) | every) }} # This won't catch a mix of .adoc and non .adoc changes, see: https://github.com/linear-b/gitstream/issues/93

is:
  formatting: {{ source.diff.files | isFormattingChange }}
  docs: {{ (files | allDocs) or (files | match(regex=r/\.adoc$/) | every) }} # This won't catch a mix of .adoc and non .adoc changes, see: https://github.com/linear-b/gitstream/issues/93
  tests: {{ files | allTests }}

  # Exclude anything under samples/snippets sourceSets, or any sort of test resource file

But you can disable it by setting `syntaxHighlight` to `False`:

```Python hl_lines="3"
{!../../../docs_src/configure_swagger_ui/tutorial001.py!}
```

...and then Swagger UI won't show the syntax highlighting anymore:

<img src="/img/tutorial/extending-openapi/image03.png">

## Change the Theme