```Python hl_lines="8  10-11"
{!> ../../../docs_src/response_model/tutorial003_02.py!}
```

This simple case is handled automatically by FastAPI because the return type annotation is the class (or a subclass) of `Response`.

And tools will also be happy because both `RedirectResponse` and `JSONResponse` are subclasses of `Response`, so the type annotation is correct.

### Annotate a Response Subclass

     * least old versions), so we mostly do. This is useful because we don't actually run our CI on
     * Windows under Java 8, at least as of this writing.
     *
     * Under Windows in particular, we want to test that:
     *
     * - Under Java 9+, createTempDir() succeeds because it can look up the *real* username, rather
     * than relying on the one from the system property.
     *

        "A device attached to the system is not functioning.",
        "The process cannot access the file because it is being used by another process.",
        "The process cannot access the file because it is being used by another process.",
        "The process cannot access the file because another process has locked a portion of the file.",
        "The disk is full.",
        "A duplicate name exists on the network.",

      // Fail fast if there's no response queued up.
      return failFastResponse!!
    }

    val result = responseQueue.take()

    // If take() returned because we're shutting down, then enqueue another dead letter so that any
    // other threads waiting on take() will also return.
    if (result == DEAD_LETTER) responseQueue.add(DEAD_LETTER)

    return result
  }

   * overkill for most Atomics because they are usually irregularly
   * scattered in memory and thus don't interfere much with each
   * other. But Atomic objects residing in arrays will tend to be
   * placed adjacent to each other, and so will most often share
   * cache lines (with a huge negative performance impact) without
   * this precaution.
   *
   * In part because Cells are relatively large, we avoid creating

     * least old versions), so we mostly do. This is useful because we don't actually run our CI on
     * Windows under Java 8, at least as of this writing.
     *
     * Under Windows in particular, we want to test that:
     *
     * - Under Java 9+, createTempDir() succeeds because it can look up the *real* username, rather
     * than relying on the one from the system property.
     *

## Standards-based benefits, alternative documentation

And because the generated schema is from the <a href="https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.1.0.md" class="external-link" target="_blank">OpenAPI</a> standard, there are many compatible tools.

  @Override
  int indexOf(@CheckForNull Object target) {
    if (!contains(target)) {
      return -1;
    }
    // The cast is safe because of the contains check—at least for any reasonable Comparable class.
    @SuppressWarnings("unchecked")
    // requireNonNull is safe because of the contains check.
    C c = (C) requireNonNull(target);
    return (int) domain.distance(first(), c);
  }

  @Override

      tester.testEquals();
    } catch (AssertionFailedError e) {
      assertErrorMessage(e, "bar [group 1, item 2] must be Object#equals to foo [group 1, item 1]");
      return;
    }
    fail("should failed because symmetry is broken");
  }

  public void testTransitivityBrokenInEqualityGroup() {
    EqualsTester tester =
        new EqualsTester()
            .addEqualityGroup(

 * family. <b>Avoid</b> creating a mock or stub {@code Future}. Mock and stub implementations are
 * fragile because they assume that only certain methods will be called and because they often
 * implement subtleties of the API improperly.
 *
 * <p><b>Custom implementation</b>: Avoid implementing {@code ListenableFuture} from scratch. If you