import os

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

/// tip

Het tweede argument van <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is de standaardwaarde die wordt geretourneerd.

Als je dit niet meegeeft, is de standaardwaarde `None`. In dit geval gebruiken we standaard `"World"`.

///

```Python hl_lines="3"
import os

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

/// tip

The second argument to <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> is the default value to return.

If not provided, it's `None` by default, here we provide `"World"` as the default value to use.

///

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

Und wenn Sie auf <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a> gehen, sehen Sie die Response von FastAPI:

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

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

E se você for até <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a>, você verá o retorno do FastAPI:

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

  }

  @Override public void onOpen(WebSocket webSocket, Response response) {
    webSocket.send("Hello...");
    webSocket.send("...World!");
    webSocket.send(ByteString.decodeHex("deadbeef"));
    webSocket.close(1000, "Goodbye, World!");
  }

  @Override public void onMessage(WebSocket webSocket, String text) {
    System.out.println("MESSAGE: " + text);
  }

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

Eğer <a href="http://localhost:8000/v2/" class="external-link" target="_blank">http://localhost:8000/v2/</a> adresine giderseniz, FastAPI'dan gelen yanıtı göreceksiniz:

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

    assert response.json() == {"message": "Hello World"}
    assert (
        response.headers["access-control-allow-origin"]
        == "https://localhost.tiangolo.com"
    )

    # Test non-CORS response
    response = client.get("/")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Hello World"}

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

And if you go to <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a> you will see the response from FastAPI:

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

app = FastAPI()


@app.api_route("/api_route")
def non_operation():
    return {"message": "Hello World"}


def non_decorated_route():
    return {"message": "Hello World"}


app.add_api_route("/non_decorated_route", non_decorated_route)


@app.get("/text")
def get_text():
    return "Hello World"


@app.get("/path/{item_id}")
def get_id(item_id):
    return item_id

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

并且如果您访问 <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a>，您将会看到由 FastAPI 返回的响应：

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