{* ../../docs_src/dependencies/tutorial008_an_py39.py hl[18:19,26:27] *}

The same way, you could have some dependencies with `yield` and some other dependencies with `return`, and have some of those depend on some of the others.

And you could have a single dependency that requires several other dependencies with `yield`, etc.

You can have any combinations of dependencies that you want.

You can verify it in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/request-form-models/image01.png">
</div>

## Forbid Extra Form Fields { #forbid-extra-form-fields }

In some special use cases (probably not very common), you might want to **restrict** the form fields to only those declared in the Pydantic model. And **forbid** any **extra** fields.

/// note

```

...this would work:

```JSON
{
    "item_id": "foo-item",
    "needy": "sooooneedy"
}
```

And of course, you can define some parameters as required, some as having a default value, and some entirely optional:

{* ../../docs_src/query_params/tutorial006_py310.py hl[8] *}

In this case, there are 3 query parameters:

* `needy`, a required `str`.

# History, Design and Future { #history-design-and-future }

Some time ago, <a href="https://github.com/fastapi/fastapi/issues/3#issuecomment-454956920" class="external-link" target="_blank">a **FastAPI** user asked</a>:

> What’s the history of this project? It seems to have come from nowhere to awesome in a few weeks [...]

Here's a little bit of that history.

## Alternatives { #alternatives }

* `internal`: Internal
    * Use this for changes that only affect how the repo is managed. For example upgrades to internal dependencies, changes in GitHub Actions or scripts, etc.

/// tip

    @Test
    public void testReset() throws Exception {
        // Create some state
        String username = "resettest";
        String ip = "192.168.1.12";

        for (int i = 0; i < 2; i++) {
            rateLimiter.checkAttempt(username, ip);
            rateLimiter.recordFailure(username, ip);
        }

        // Should have some state

# Apprendre

Voici les sections introductives et les tutoriels pour apprendre **FastAPI**.

**projects depend on**. That's very difficult to manage. And you would probably end up running some projects with some **incompatible versions** of the packages, and not knowing why something isn't working.

Also, depending on your operating system (e.g. Linux, Windows, macOS), it could have come with Python already installed. And in that case it probably had some packages pre-installed with some specific versions **needed by your system**. If you install packages in the global Python environment,...

## Codes HTTP supplémentaires

Si vous souhaitez renvoyer des codes HTTP supplémentaires en plus du code principal, vous pouvez le faire en renvoyant directement une `Response`, comme une `JSONResponse`, et en définissant directement le code HTTP supplémentaire.

Par exemple, disons que vous voulez avoir un *chemin d'accès* qui permet de mettre à jour les éléments et renvoie les codes HTTP 200 "OK" en cas de succès.

            }
            // Simulate some encoding activity on the buffer
            dst.enc_ndr_long(123);
        }

        @Override
        public void decode(NdrBuffer src) throws NdrException {
            if (throwOnDecode) {
                throw new NdrException("Failed to decode");
            }
            // Simulate some decoding activity on the buffer
            src.dec_ndr_long();