Luego, cuando creas una instance de esa clase `Settings` (en este caso, en el objeto `settings`), Pydantic leerá las variables de entorno de una manera indiferente a mayúsculas y minúsculas, por lo que una variable en mayúsculas `APP_NAME` aún será leída para el atributo `app_name`.

Luego convertirá y validará los datos. Así que, cuando uses ese objeto `settings`, tendrás datos de los tipos que declaraste (por ejemplo, `items_per_user` será un `int`).

<resources>
  <string name="app_name">android-test</string>

<resources>
  <string name="app_name">regression-test</string>

from pydantic_settings import BaseSettings


class Settings(BaseSettings):
    app_name: str = "Awesome API"
    admin_email: str
    items_per_user: int = 50

from pydantic.v1 import BaseSettings


class Settings(BaseSettings):
    app_name: str = "Awesome API"
    admin_email: str
    items_per_user: int = 50

    class Config:

from pydantic_settings import BaseSettings


class Settings(BaseSettings):
    app_name: str = "Awesome API"
    admin_email: str

app.dependency_overrides[get_settings] = get_settings_override


def test_app():
    response = client.get("/info")
    data = response.json()
    assert data == {
        "app_name": "Awesome API",
        "admin_email": "******@****.***",
        "items_per_user": 50,

app.dependency_overrides[get_settings] = get_settings_override


def test_app():
    response = client.get("/info")
    data = response.json()
    assert data == {
        "app_name": "Awesome API",
        "admin_email": "******@****.***",
        "items_per_user": 50,

    return mod.app


def test_settings(app):
    client = TestClient(app)
    response = client.get("/info")
    assert response.status_code == 200, response.text
    assert response.json() == {
        "app_name": "Awesome API",
        "admin_email": "******@****.***",
        "items_per_user": 50,

///

Then, when you create an instance of that `Settings` class (in this case, in the `settings` object), Pydantic will read the environment variables in a case-insensitive way, so, an upper-case variable `APP_NAME` will still be read for the attribute `app_name`.

Next it will convert and validate the data. So, when you use that `settings` object, you will have data of the types you declared (e.g. `items_per_user` will be an `int`).