{* ../../docs_src/python_types/tutorial004.py hl[2] *}

## 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

You can declare all the standard Python types, not only `str`.

You can use, for example:

* `int`
* `float`
* `bool`
* `bytes`

# Cookie Parameter Models

If you have a group of **cookies** that are related, you can create a **Pydantic model** to declare them. 🍪

This would allow you to **re-use the model** in **multiple places** and also to declare validations and metadata for all the parameters at once. 😎

/// note

This is supported since FastAPI version `0.115.0`. 🤓

///

/// tip

This same technique applies to `Query`, `Cookie`, and `Header`. 😎

///

///

/// tip

To declare File bodies, you need to use `File`, because otherwise the parameters would be interpreted as query parameters or body (JSON) parameters.

///

The files will be uploaded as "form data".

{!../../docs_src/path_operation_advanced_configuration/tutorial004.py!}
```

## Additional Responses

You probably have seen how to declare the `response_model` and `status_code` for a *path operation*.

That defines the metadata about the main response of a *path operation*.

You can also declare additional responses with their models, status codes, etc.

# Path Parameters

You can declare path "parameters" or "variables" with the same syntax used by Python format strings:

```Python hl_lines="6-7"
{!../../docs_src/path_params/tutorial001.py!}
```

The value of the path parameter `item_id` will be passed to your function as the argument `item_id`.

But you still want to be able to filter and convert the data you return with a `response_model`.

For those cases, you can use a `Response` parameter.

## Use a `Response` parameter

You can declare a parameter of type `Response` in your *path operation function* (as you can do for cookies and headers).

And then you can set the `status_code` in that *temporal* response object.

```Python hl_lines="1  9  12"

# Declare Request Example Data

You can declare examples of the data your app can receive.

Here are several ways to do it.

## Extra JSON Schema data in Pydantic models

You can declare `examples` for a Pydantic model that will be added to the generated JSON Schema.

//// tab | Python 3.10+ Pydantic v2

```Python hl_lines="13-24"
{!> ../../docs_src/schema_extra_example/tutorial001_py310.py!}
```

////

/// tip

If you have strict type checks in your editor, mypy, etc, you can declare the function return type as `Any`.

That way you tell the editor that you are intentionally returning anything. But FastAPI will still do the data documentation, validation, filtering, etc. with the `response_model`.

///

### `response_model` Priority

/// note | Nota

Isso é suportado desde o FastAPI versão `0.115.0`. 🤓

///

## Parâmetros de Consulta com um Modelo Pydantic

Declare os **parâmetros de consulta** que você precisa em um **modelo Pydantic**, e então declare o parâmetro como `Query`:

//// tab | Python 3.10+

```Python hl_lines="9-13  17"
{!> ../../docs_src/query_param_models/tutorial001_an_py310.py!}
```

////

Les paramètres de la fonction seront reconnus comme tel :

* Si le paramètre est aussi déclaré dans le **chemin**, il sera utilisé comme paramètre de chemin.
* Si le paramètre est d'un **type singulier** (comme `int`, `float`, `str`, `bool`, etc.), il sera interprété comme un paramètre de **requête**.
* Si le paramètre est déclaré comme ayant pour type un **modèle Pydantic**, il sera interprété comme faisant partie du **corps** de la requête.