## Como Parece

Vamos primeiro usar o código e ver como funciona, e depois voltaremos para entender o que está acontecendo.

## Crie um `main.py`
Copie o exemplo em um arquivo `main.py`:

{* ../../docs_src/security/tutorial001.py *}

## Execute-o

/// info | informação



///

INFO:     Application startup complete.
```

</div>

<details markdown="1">
<summary>關於指令 <code>uvicorn main:app --reload</code>...</summary>

該指令 `uvicorn main:app` 指的是：

- `main`：`main.py` 檔案（一個 python 的 "模組"）。
- `app`：在 `main.py` 檔案中，使用 `app = FastAPI()` 建立的物件。
- `--reload`：程式碼更改後會自動重新啟動，請僅在開發時使用此參數。

</details>

### 檢查

<details markdown="1">
<summary>À propos de la commande <code>uvicorn main:app --reload</code> ...</summary>

La commande `uvicorn main:app` fait référence à :

* `main` : le fichier `main.py` (le "module" Python).
* `app` : l'objet créé à l'intérieur de `main.py` avec la ligne `app = FastAPI()`.
* `--reload` : fait redémarrer le serveur après des changements de code. À n'utiliser que pour le développement.

</details>

![Events Diagram](../assets/images/******@****.***)

Here’s a [sample event listener](https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/PrintEventsNonConcurrent.java) that prints each event with a timestamp.

```java
class PrintingEventListener extends EventListener {
  private long callStartNanos;

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package main

import (
	"bytes"
	"context"
	"crypto/rand"
	"encoding/base64"
	"encoding/json"
	"errors"
	"flag"
	"fmt"
	"log"
	"net/http"
	"net/url"
	"strings"
	"time"

	"golang.org/x/oauth2"

RUN pip install --no-cache-dir --upgrade -r /code/requirements.txt

# (1)
COPY ./main.py /code/

# (2)
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "80"]
```

1. main.py`ファイルを `/code` ディレクトリに直接コピーします。

2. Uvicornを実行し、`main`から`app`オブジェクトをインポートするように指示します（`app.main`からインポートするのではなく）。

次にUvicornコマンドを調整して、`app.main` の代わりに新しいモジュール `main` を使用し、FastAPIオブジェクトである `app` をインポートします。

## デプロイメントのコンセプト

      System.out.println("Server: " + response.header("Server"));
      System.out.println("Date: " + response.header("Date"));
      System.out.println("Vary: " + response.headers("Vary"));
    }
  }

  public static void main(String... args) throws Exception {
    new AccessHeaders().run();
  }

        userAgent = userAgent.name,
        version = userAgent.version,
        platform = userAgent.platform,
        enabled = userAgent.suiteNames.map { SuiteId(null, it) },
      )
    }
}

suspend fun main() {
  val sslLabsClient =
    SslLabsClient(
      callFactory = OkHttpClient(),
    )

  for (client in sslLabsClient.clients()) {
    println(client)
  }

{* ../../docs_src/sub_applications/tutorial001.py hl[11, 19] *}

### Revisa la documentación automática de la API

Ahora, ejecuta el comando `fastapi` con tu archivo:

<div class="termy">

```console
$ fastapi dev main.py

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

    )
    assertInvalid(
      "text/plain; a=\u2025",
      "Parameter is not formatted correctly: \"a=‥\" for: \"text/plain; a=‥\"",
    )
    assertInvalid(
      "text/pl ain",
      "Parameter is not formatted correctly: \" ain\" for: \"text/pl ain\"",
    )
    assertInvalid(
      "text/plain ",
      "Parameter is not formatted correctly: \" \" for: \"text/plain \"",
    )
    assertInvalid(