*     JVM
   * @return an unmodifiable version of the input which will not hang the JVM
   * @since 28.0 (but only since 33.4.0 in the Android flavor)
   */
  @J2ktIncompatible
  @GwtIncompatible // TODO
  public static ExecutorService getExitingExecutorService(
      ThreadPoolExecutor executor, Duration terminationTimeout) {
    return getExitingExecutorService(

  /**
   * Returns the equivalent {@code com.google.common.base.Optional} value to the given {@code
   * java.util.Optional}, or {@code null} if the argument is null.
   *
   * @since NEXT (but since 21.0 in the JRE flavor)
   */
  @SuppressWarnings("Java7ApiChecker")
  @IgnoreJRERequirement // Users will use this only if they're already using Optional.
  @CheckForNull

números)",badAlphaNumericExtra:" e",wrongFileSize:"O arquivo selecionado é maior que o tamanho máximo permitido (%s)",wrongFileType:"Somente arquivos %s são permitidos",groupCheckedRangeStart:"Por favor, escolha entre ",groupCheckedTooFewStart:"Por favor, escolha pelo menos ",groupCheckedTooManyStart:"Por favor, escolhe no máximo ",groupCheckedEnd:" alternativa(s)",badCreditCard:"O número de cartão de crédito digitado não é válido",badCVV:"O código de segurança do cartão de crédito não é válido",wrongFileDim:"As...

   * @throws IllegalStateException if the service manager reaches a state from which it cannot
   *     become {@linkplain #isHealthy() healthy}.
   * @since NEXT (but since 28.0 in the JRE flavor)
   */
  @SuppressWarnings("Java7ApiChecker")
  @IgnoreJRERequirement // Users will use this only if they're already using Duration.
  public void awaitHealthy(Duration timeout) throws TimeoutException {

   * @throws IllegalStateException if the service manager reaches a state from which it cannot
   *     become {@linkplain #isHealthy() healthy}.
   * @since 28.0 (but only since 33.4.0 in the Android flavor)
   */
  public void awaitHealthy(Duration timeout) throws TimeoutException {
    awaitHealthy(toNanosSaturated(timeout), TimeUnit.NANOSECONDS);
  }

  /**

  private final TypeToken<?> type;
  private final ImmutableList<Annotation> annotations;

  /**
   * An {@code AnnotatedType} instance, or {@code null} under Android VMs (possible only when using
   * the Android flavor of Guava). The field is declared with a type of {@code Object} to avoid
   * compatibility problems on Android VMs. The corresponding accessor method, however, can have the

			return fmt.Errorf("could not build port forwarder for %s: %v", flavor, err)
		}

		if err = fw.Start(); err != nil {
			fw.Close()
			// Try the next port
			continue
		}

		// Close the port forwarder when the command is terminated.
		ClosePortForwarderOnInterrupt(fw)

		log.Debugf(fmt.Sprintf("port-forward to %s pod ready", flavor))
		openBrowser(fmt.Sprintf(urlFormat, fw.Address()), writer, browser)

So, even with the code above that doesn't use Pydantic explicitly, FastAPI is using Pydantic to convert those standard dataclasses to Pydantic's own flavor of dataclasses.

And of course, it supports the same:

* data validation
* data serialization
* data documentation, etc.

     * @param delay the delay between the termination of one execution and the commencement of the
     *     next
     * @since 28.0 (but only since 33.4.0 in the Android flavor)
     */
    public static Scheduler newFixedDelaySchedule(Duration initialDelay, Duration delay) {
      return newFixedDelaySchedule(
          toNanosSaturated(initialDelay), toNanosSaturated(delay), NANOSECONDS);

   * @throws IllegalArgumentException if {@code permitsPerSecond} is negative or zero or {@code
   *     warmupPeriod} is negative
   * @since 28.0 (but only since 33.4.0 in the Android flavor)
   */
  public static RateLimiter create(double permitsPerSecond, Duration warmupPeriod) {
    return create(permitsPerSecond, toNanosSaturated(warmupPeriod), TimeUnit.NANOSECONDS);
  }

  /**