def run(playwright: Playwright) -> None:
    browser = playwright.chromium.launch(headless=False)
    context = browser.new_context(viewport={"width": 960, "height": 1080})
    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_text("GET/items/Read Items").click()
    page.get_by_role("tab", name="Schema").click()
    page.get_by_label("Schema").get_by_role("button", name="Expand all").click()

**FastAPI** is not actually an alternative to **Requests**. Their scope is very different.

It would actually be common to use Requests *inside* of a FastAPI application.

But still, FastAPI got quite some inspiration from Requests.

**Requests** is a library to *interact* with APIs (as a client), while **FastAPI** is a library to *build* APIs (as a server).

def run(playwright: Playwright) -> None:
    browser = playwright.chromium.launch(headless=False)
    context = browser.new_context(viewport={"width": 960, "height": 1080})
    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_text("GET/items/Read Items").click()
    page.get_by_role("button", name="Try it out").click()
    page.get_by_role("button", name="Execute").click()
    page.screenshot(

    password = user_dict["password"],
    email = user_dict["email"],
    full_name = user_dict["full_name"],
)
```

#### A Pydantic model from the contents of another

As in the example above we got `user_dict` from `user_in.dict()`, this code:

```Python
user_dict = user_in.dict()
UserInDB(**user_dict)
```

would be equivalent to:

```Python
UserInDB(**user_in.dict())
```

def run(playwright: Playwright) -> None:
    browser = playwright.chromium.launch(headless=False)
    context = browser.new_context(viewport={"width": 960, "height": 1080})
    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_role("button", name="Item-Input").click()
    page.get_by_role("button", name="Item-Output").click()
    page.set_viewport_size({"width": 960, "height": 820})
    page.screenshot(

#### The time to answer helps the attackers

At that point, by noticing that the server took some microseconds longer to send the "Incorrect username or password" response, the attackers will know that they got _something_ right, some of the initial letters were right.

And then they can try again knowing that it's probably something more similar to `stanleyjobsox` than to `johndoe`.

#### A "professional" attack

def run(playwright: Playwright) -> None:
    browser = playwright.chromium.launch(headless=False)
    context = browser.new_context(viewport={"width": 960, "height": 1080})
    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_text("POST/items/Create Item").click()
    page.get_by_role("tab", name="Schema").first.click()
    page.screenshot(

        match=(
            "Cannot specify a FastAPI annotation in `Annotated` and `Depends` as a"
            " default value together for 'foo'"
        ),
    ):

        @app.get("/")
        async def get3(foo: Annotated[int, Query(min_length=1)] = Depends(dep)):
            pass  # pragma: nocover

    client = TestClient(app)
    response = client.get("/multi-query", params={"foo": "5"})
    assert response.status_code == 200

!!! tip
    The `shutdown` would happen when you are **stopping** the application.

    Maybe you need to start a new version, or you just got tired of running it. 🤷

### Lifespan function

The first thing to notice, is that we are defining an async function with `yield`. This is very similar to Dependencies with `yield`.

```Python hl_lines="14-19"

def run(playwright: Playwright) -> None:
    browser = playwright.chromium.launch(headless=False)
    context = browser.new_context(viewport={"width": 960, "height": 1080})
    page = context.new_page()
    page.goto("http://localhost:8000/docs")
    page.get_by_role("button", name="Item", exact=True).click()
    page.set_viewport_size({"width": 960, "height": 700})
    page.screenshot(