For example, you could want to **return a dictionary** or a database object, but **declare it as a Pydantic model**. This way the Pydantic model would do all the data documentation, validation, etc. for the object that you returned (e.g. a dictionary or database object).

     *
     * - Any kind of Error from a listener. Even if we could distinguish that case (by exposing some
     * extra state from AbstractFuture), our options are limited: A call to setException() would be
     * a no-op. We could log, but if that's what we really want, we should modify
     * AbstractFuture.executeListener to do so, since that method would have the ability to continue
     * to execute other listeners.
     *

You could load it at the top level of the module/file, but that would also mean that it would **load the model** even if you are just running a simple automated test, then that test would be **slow** because it would have to wait for the model to load before being able to run an independent part of the code.

 * and memory footprint. For example, if a set of tasks are CPU-bound, one could easily create a
 * very compact {@code Striped<Lock>} of {@code availableProcessors() * 4} stripes, instead of
 * possibly thousands of locks which could be created in a {@code Map<K, Lock>} structure.
 *
 * @author Dimitris Andreou
 * @since 13.0
 */
@J2ktIncompatible
@GwtIncompatible

## Custom CDN for JavaScript and CSS { #custom-cdn-for-javascript-and-css }

Let's say that you want to use a different <abbr title="Content Delivery Network">CDN</abbr>, for example you want to use `https://unpkg.com/`.

This could be useful if for example you live in a country that restricts some URLs.

### Disable the automatic docs { #disable-the-automatic-docs }

The first step is to disable the automatic docs, as by default, those use the default CDN.

This client could be a browser with a frontend, a code from someone else, an IoT device, etc.

You could need to tell the client that:

* The client doesn't have enough privileges for that operation.
* The client doesn't have access to that resource.
* The item the client was trying to access doesn't exist.
* etc.

    could use new flow control capacity before acknowledging it, causing strict HTTP/2 servers to
    fail the call.

 *  Fix: Recover gracefully when a coalesced connection immediately goes unhealthy.

## Version 3.14.2

_2019-05-19_

 *  Fix: Lock in a route when recovering from an HTTP/2 connection error. We had a bug where two
    calls that failed at the same time could cause OkHttp to crash with a `NoSuchElementException`

   * FeatureSpecificTestSuiteBuilder.suppressing()}.
   */
  /*
   * TODO(cpovirk): or we could make HOLES_FORBIDDEN a feature. Or we could declare that
   * implementations are permitted to throw IAE if a hole is requested, and we could update
   * test*Hole to permit IAE. (But might this ignore genuine bugs?) But see the TODO above
   * testLower, which could make this all unnecessary
   */
  public static Method[] getHoleMethods() {

 * a file or directory that would be more accessible.
 */
@J2ktIncompatible
@GwtIncompatible
@J2ObjCIncompatible
abstract class TempFileCreator {
  static final TempFileCreator INSTANCE = pickSecureCreator();

  /**
   * @throws IllegalStateException if the directory could not be created (to implement the contract

You import it and create an "instance" the same way you would with the class `FastAPI`:

{* ../../docs_src/bigger_applications/app_an_py39/routers/users.py hl[1,3] title["app/routers/users.py"] *}

### *Path operations* with `APIRouter` { #path-operations-with-apirouter }

And then you use it to declare your *path operations*.

Use it the same way you would use the `FastAPI` class: