# Corpo - Modelos aninhados

Com o **FastAPI**, você pode definir, validar, documentar e usar modelos profundamente aninhados de forma arbitrária (graças ao Pydantic).

## Campos do tipo Lista

Você pode definir um atributo como um subtipo. Por exemplo, uma `list` do Python:

```Python hl_lines="14"
{!../../docs_src/body_nested_models/tutorial001.py!}
```

If you are working with **FastAPI** you don't have to worry about that, because that "first" function will be your *path operation function*, and FastAPI will know how to do the right thing.

But if you want to use `async` / `await` without FastAPI, you can do it as well.

### Write your own async code

To do that, we declare a method `__call__`:

{* ../../docs_src/dependencies/tutorial011_an_py39.py hl[12] *}

In this case, this `__call__` is what **FastAPI** will use to check for additional parameters and sub-dependencies, and this is what will be called to pass a value to the parameter in your *path operation function* later.

## Parameterize the instance

from fastapi.testclient import TestClient

from docs_src.custom_response.tutorial007 import app

client = TestClient(app)


def test_get():
    fake_content = b"some fake video bytes"
    response = client.get("/")

import pytest
from fastapi.exceptions import FastAPIError
from fastapi.testclient import TestClient


@pytest.fixture(name="client")
def get_client():
    from docs_src.dependencies.tutorial008c_an import app

    client = TestClient(app)
    return client


def test_get_no_item(client: TestClient):
    response = client.get("/items/foo")
    assert response.status_code == 404, response.text

import pytest
from fastapi.testclient import TestClient

from docs_src.path_operation_configuration.tutorial006 import app

client = TestClient(app)


@pytest.mark.parametrize(
    "path,expected_status,expected_response",
    [
        ("/items/", 200, [{"name": "Foo", "price": 42}]),
        ("/users/", 200, [{"username": "johndoe"}]),
        ("/elements/", 200, [{"item_id": "Foo"}]),
    ],
)

from fastapi import APIRouter

router = APIRouter()


@router.get("/users/", tags=["users"])
async def read_users():
    return [{"username": "Rick"}, {"username": "Morty"}]


@router.get("/users/me", tags=["users"])
async def read_user_me():
    return {"username": "fakecurrentuser"}


@router.get("/users/{username}", tags=["users"])
async def read_user(username: str):

from fastapi.testclient import TestClient

from docs_src.security.tutorial001_an import app

client = TestClient(app)


def test_no_token():
    response = client.get("/items")
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Bearer"


def test_token():

from fastapi.testclient import TestClient

from docs_src.response_cookies.tutorial001 import app

client = TestClient(app)


def test_path_operation():
    response = client.post("/cookie/")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Come to the dark side, we have cookies"}

# 🛠️

👆 💪 🚮 🛠️ **FastAPI** 🈸.

"🛠️" 🔢 👈 👷 ⏮️ 🔠 **📨** ⏭ ⚫️ 🛠️ 🙆 🎯 *➡ 🛠️*. & ⏮️ 🔠 **📨** ⏭ 🛬 ⚫️.

* ⚫️ ✊ 🔠 **📨** 👈 👟 👆 🈸.
* ⚫️ 💪 ⤴️ 🕳 👈 **📨** ⚖️ 🏃 🙆 💪 📟.
* ⤴️ ⚫️ 🚶‍♀️ **📨** 🛠️ 🎂 🈸 ( *➡ 🛠️*).
* ⚫️ ⤴️ ✊ **📨** 🏗 🈸 ( *➡ 🛠️*).
* ⚫️ 💪 🕳 👈 **📨** ⚖️ 🏃 🙆 💪 📟.
* ⤴️ ⚫️ 📨 **📨**.

/// note | "📡 ℹ"

🚥 👆 ✔️ 🔗 ⏮️ `yield`, 🚪 📟 🔜 🏃 *⏮️* 🛠️.

🚥 📤 🙆 🖥 📋 (📄 ⏪), 👫 🔜 🏃 *⏮️* 🌐 🛠️.