{*../../docs_src/python_types/tutorial009.py hl[1,4] *}

Utiliser `Optional[str]` plutôt que `str` permettra à l'éditeur de vous aider à détecter les erreurs où vous supposeriez qu'une valeur est toujours de type `str`, alors qu'elle pourrait aussi être `None`.

#### Types génériques

If there is no associated issue, then write "N/A".
-->

#### Special notes for your reviewer:

#### Does this PR introduce a user-facing change?
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        channel = "flakiness-detection",
        extraParameters = "--checks none --rerun --cross-version-only",
    ),
    AD_HOC(
        displayName = "AdHoc Performance Test",
        timeout = 30,
        channel = "adhoc",
        extraParameters = "--checks none",
    ),
}

enum class Trigger {
    NEVER,
    EACH_COMMIT,
    DAILY,
    WEEKLY,
}

     */
    @Nonnull
    List<Exception> getExceptions();

    /**
     * Gets the root node of the dependency graph.
     *
     * @return the root node of the dependency graph or {@code null} if none
     */
    @Nullable
    Node getRoot();

    /**
     * The ordered list of the flattened dependency nodes.
     *
     * @return the ordered list of the flattened dependency nodes
     */
    @Nonnull

    internal var eventListenerFactory: EventListener.Factory = EventListener.NONE.asFactory()
    internal var retryOnConnectionFailure = true
    internal var fastFallback = true
    internal var authenticator: Authenticator = Authenticator.NONE
    internal var followRedirects = true
    internal var followSslRedirects = true

      .assertRequestHeader("Accept-Language", "en-US")
      .assertRequestHeader("Accept-Charset", "UTF-8")
      .assertRequestHeader("If-None-Match") // No If-None-Match on the user's request.
      .assertSentRequestAtMillis(request2SentAt, request2ReceivedAt)
      .assertReceivedResponseAtMillis(request2SentAt, request2ReceivedAt)

re(e,t){for(var n,r,i,o,a,s,u,l=[],c=0,f=e.length;c<f;c++)(r=e[c]).style&&(n=r.style.display,t?("none"===n&&(l[c]=_.get(r,"display")||null,l[c]||(r.style.display="")),""===r.style.display&&ee(r)&&(l[c]=(u=a=o=void 0,a=(i=r).ownerDocument,s=i.nodeName,(u=ne[s])||(o=a.body.appendChild(a.createElement(s)),u=ce.css(o,"display"),o.parentNode.removeChild(o),"none"===u&&(u="block"),ne[s]=u)))):"none"!==n&&(l[c]="none",_.set(r,"display",n)));for(c=0;c<f;c++)null!=l[c]&&(e[c].style.display=l[c]);return e}ce.f...

        description =
            "Command line option for the performance test task to enable profiling. " +
                "For example `async-profiler`, `async-profiler-heap`, `async-profiler-all` or `jfr`. Use `none` for benchmarking only.",
    )
}

object AdHocPerformanceScenarioLinux : AdHocPerformanceScenario(Os.LINUX)

object AdHocPerformanceScenarioWindows : AdHocPerformanceScenario(Os.WINDOWS)

  SUBSET_VIEW,
  DESCENDING_VIEW,

  /**
   * For documenting collections that support no optional features, such as {@link
   * java.util.Collections#emptySet}
   */
  NONE;

  private final Set<Feature<? super Collection>> implied;

  CollectionFeature(Feature<? super Collection>... implied) {
    this.implied = copyToSet(implied);
  }

  @Override

     *
     * @param artifact The artifact whose available versions should be determined, must not be {@code null}.
     * @return The available versions of the artifact or an empty list if none, never {@code null}.
     * @since 3.0-alpha-3
     */
    List<String> findVersions(Artifact artifact);

    /**