@router.route("/items/")
def read_items(request: Request):
    return JSONResponse({"hello": "world"})


app.include_router(router)

client = TestClient(app)


def test_sub_router():
    response = client.get("/items/")
    assert response.status_code == 200, response.text

Якщо ви запустите це й перейдете на [http://localhost:8000/v1/](http://localhost:8000/v1/), ви побачите відповідь від Flask:

```txt
Hello, World from Flask!
```

А якщо ви перейдете на [http://localhost:8000/v2](http://localhost:8000/v2), ви побачите відповідь від FastAPI:

```JSON
{
    "message": "Hello World"
}

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip | Tipp

Das zweite Argument von [`os.getenv()`](https://docs.python.org/3.8/library/os.html#os.getenv) ist der Defaultwert, der zurückgegeben wird.

Wenn er nicht angegeben wird, ist er standardmäßig `None`. Hier geben wir „World“ als den zu verwendenden Defaultwert an.

///

Si lo ejecutas y vas a [http://localhost:8000/v1/](http://localhost:8000/v1/) verás el response de Flask:

```txt
Hello, World from Flask!
```

Y si vas a [http://localhost:8000/v2](http://localhost:8000/v2) verás el response de FastAPI:

```JSON
{
    "message": "Hello World"
}

                                                       askance--
Said he thanked the whiting kindly, but he would not join the
   dance.
    Would not, could not, would not, could not, would not join
        the dance.
    Would not, could not, would not, could not, could not join
        the dance.

`"What matters it how far we go?" his scaly friend replied.

@app.get("/", dependencies=[Depends(parent_dep)])
async def get_main():
    return {"msg": "Hello World"}


client = TestClient(app)


def test_dependency_set_status_code():
    response = client.get("/")
    assert response.status_code == 201, response.text

        });
    assertThat(orig.toString())
        .contains("Exception thrown from implementation: class java.lang.StackOverflowError");
  }

  // Regression test for a case where we would fail to execute listeners immediately on done futures
  // this would be observable from an afterDone callback
  public void testListenersExecuteImmediately_fromAfterDone() {
    AbstractFuture<String> f =
        new AbstractFuture<String>() {

This is what you would want to do in **most cases**, for example:

* Using **Kubernetes** or similar tools
* When running on a **Raspberry Pi**
* Using a cloud service that would run a container image for you, etc.

### Package Requirements { #package-requirements }

You would normally have the **package requirements** for your application in some file.

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip | Astuce

Le deuxième argument de [`os.getenv()`](https://docs.python.org/3.8/library/os.html#os.getenv) est la valeur par défaut à retourner.

S'il n'est pas fourni, c'est `None` par défaut ; ici, nous fournissons `"World"` comme valeur par défaut à utiliser.

///

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip | İpucu

[`os.getenv()`](https://docs.python.org/3.8/library/os.html#os.getenv) fonksiyonunun ikinci argümanı, bulunamadığında döndürülecek varsayılan (default) değerdir.

Verilmezse varsayılan olarak `None` olur; burada varsayılan değer olarak `"World"` verdik.

///