# Including WSGI - Flask, Django, others { #including-wsgi-flask-django-others }

You can mount WSGI applications as you saw with [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}, [Behind a Proxy](behind-a-proxy.md){.internal-link target=_blank}.

For that, you can use the `WSGIMiddleware` and use it to wrap your WSGI application, for example, Flask, Django, etc.

## Using `WSGIMiddleware` { #using-wsgimiddleware }

When deploying applications you will probably want to have some **replication of processes** to take advantage of **multiple cores** and to be able to handle more requests.

As you saw in the previous chapter about [Deployment Concepts](concepts.md){.internal-link target=_blank}, there are multiple strategies you can use.

And the `items_per_user` would keep its default value of `50`.

## Settings in another module { #settings-in-another-module }

You could put those settings in another module file as you saw in [Bigger Applications - Multiple Files](../tutorial/bigger-applications.md){.internal-link target=_blank}.

For example, you could have a file `config.py` with:

{* ../../docs_src/settings/app01_py39/config.py *}

          case STOPPING:
          case TERMINATED:
          case FAILED:
            // These cases are impossible due to the if statement above.
            throw new AssertionError("isStoppable is incorrectly implemented, saw: " + previous);
        }
      } catch (Throwable shutdownFailure) {
        restoreInterruptIfIsInterruptedException(shutdownFailure);
        notifyFailed(shutdownFailure);
      } finally {

* `title`
* `description`
* `deprecated`

Validations specific for strings:

* `min_length`
* `max_length`
* `pattern`

Custom validations using `AfterValidator`.

In these examples you saw how to declare validations for `str` values.

          case STOPPING:
          case TERMINATED:
          case FAILED:
            // These cases are impossible due to the if statement above.
            throw new AssertionError("isStoppable is incorrectly implemented, saw: " + previous);
        }
      } catch (Throwable shutdownFailure) {
        restoreInterruptIfIsInterruptedException(shutdownFailure);
        notifyFailed(shutdownFailure);
      } finally {

**FastAPI** uses them internally to achieve this.

///

## Dependencies with `yield` and `HTTPException` { #dependencies-with-yield-and-httpexception }

You saw that you can use dependencies with `yield` and have `try` blocks that try to execute some code and then run some exit code after `finally`.

You can also use `except` to catch the exception that was raised and do something with it.

Now you know that you have to fix it, convert `age` to a string with `str(age)`:

{* ../../docs_src/python_types/tutorial004_py39.py hl[2] *}

## Declaring types { #declaring-types }

You just saw the main place to declare type hints. As function parameters.

This is also the main place you would use them with **FastAPI**.

### Simple types { #simple-types }

    val elapsedUntilFailure = System.nanoTime() - closeAtNanos
    assertThat(TimeUnit.NANOSECONDS.toMillis(elapsedUntilFailure).toDouble())
      .isCloseTo(500.0, 250.0)

    // Close the server and confirm it saw what we expected.
    server.close(1000, null)
    serverListener.assertClosed(1000, "goodbye")
  }

  @Test
  fun webSocketsDontTriggerEventListener() {
    val eventRecorder = EventRecorder()
    client =

    }
    cache.invalidateAll();
    tasksFinished.await();

    // Check all of the removal notifications we received: they should have had correctly-associated
    // keys and values. (An earlier bug saw removal notifications for in-progress computations,
    // which had real keys with null values.)
    Map<String, String> removalNotifications = new HashMap<>();