{* ../../docs_src/bigger_applications/app_an_py39/main.py hl[1,3,7] title["app/main.py"] *}

### Importe o `APIRouter` { #import-the-apirouter }

Agora importamos os outros submódulos que possuem `APIRouter`s:

{* ../../docs_src/bigger_applications/app_an_py39/main.py hl[4:5] title["app/main.py"] *}

{* ../../docs_src/websockets/tutorial001_py39.py hl[48:52] *}

Você pode receber e enviar dados binários, de texto e JSON.

## Tente { #try-it }

Se seu arquivo for nomeado `main.py`, execute sua aplicação com:

<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>

// 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 (
	"encoding/json"
	"errors"
	"fmt"
	"log"
	"net/http"
)

func writeErrorResponse(w http.ResponseWriter, err error) {
	w.WriteHeader(http.StatusBadRequest)

#                                                     ------
# Does it send mock mail? (true: no send actually, logging only)
mail.send.mock = false

# SMTP server settings for main: host:port
mail.smtp.server.main.host.and.port = localhost:25

# The prefix of subject to show test environment or not
mail.subject.test.prefix = 

# The common return path of all mail
mail.return.path = root@localhost

#                                                     ------
# Does it send mock mail? (true: no send actually, logging only)
mail.send.mock = false

# SMTP server settings for main: host:port
mail.smtp.server.main.host.and.port = localhost:25

# The prefix of subject to show test environment or not
mail.subject.test.prefix = 

# The common return path of all mail
mail.return.path = root@localhost

 * limitations under the License.
 */

import gradlebuild.configureAsRuntimeJarClasspath

plugins {
    java
}

interface LaunchableJar {
    /**
     * The main class for the application. Can be undefined.
     */
    val mainClassName: Property<String>
}

val app = extensions.create<LaunchableJar>("app")

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev <u style="text-decoration-style:single">main.py</u>
<font color="#3465A4">INFO    </font> Using path <font color="#3465A4">main.py</font>
<font color="#3465A4">INFO    </font> Resolved absolute path <font color="#75507B">/home/user/code/awesomeapp/</font><font color="#AD7FA8">main.py</font>

 *
 * @since 4.0.0
 */
@Experimental
@Immutable
@SuppressWarnings("checkstyle:InterfaceIsType")
public interface ProjectScope extends ExtensibleEnum {

    /**
     * Main scope.
     */
    ProjectScope MAIN = projectScope("main");

    /**
     * Test scope.
     */
    ProjectScope TEST = projectScope("test");

# Advanced User Guide { #advanced-user-guide }

## Additional Features { #additional-features }

The main [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} should be enough to give you a tour through all the main features of **FastAPI**.

In the next sections you will see other options, configurations, and additional features.

/// tip

The next sections are **not necessarily "advanced"**.

```

</div>

/// note | Hinweis

Der Befehl `uvicorn main:app` bezieht sich auf:

* `main`: die Datei `main.py` (das Python-„Modul“).
* `app`: das Objekt, das innerhalb von `main.py` mit der Zeile `app = FastAPI()` erstellt wurde.

Es ist äquivalent zu:

```Python
from main import app
```

///