## Technical Details { #technical-details }

The class `BackgroundTasks` comes directly from <a href="https://www.starlette.dev/background/" class="external-link" target="_blank">`starlette.background`</a>.

It is imported/included directly into FastAPI so that you can import it from `fastapi` and avoid accidentally importing the alternative `BackgroundTask` (without the `s` at the end) from `starlette.background`.

</div>

那么文件中由 Python 自动创建的内部变量 `__name__`，会将字符串 `"__main__"` 作为值。

所以，下面这部分代码才会运行：

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

---

如果你是导入这个模块（文件）就不会这样。

因此，如果你的另一个文件 `importer.py` 像这样：

```Python
from myapp import app

# Some more code
```

在这种情况下，`myapp.py` 内部的自动变量不会有值为 `"__main__"` 的变量 `__name__`。

所以，下面这一行不会被执行：

```Python

### Target language

Translate to Portuguese (Português).

Language code: pt.

For instructions or titles in imperative, keep them in imperative, for example "Import FastAPI" to "Importe o FastAPI".

Keep existing translations as they are if the term is already translated.

                }
            }
        }

        if (trackingFile == null) {
            return; // parent or imported bom ?
        }
        try {
            Files.createDirectories(trackingDir);

            trackingData.add("");
            if (!missing) {
                if (event.getRepository() != null) {

# sets the __all__ variable. If it does, we have to be sure to add
# "contrib".
if "__all__" in vars():
  vars()["__all__"].append("contrib")

from tensorflow.python.platform import flags
# The "app" module will be imported as part of the placeholder section above.
_current_module.app.flags = flags  # pylint: disable=undefined-variable
setattr(_current_module, "flags", flags)

_major_api_version = 1

	// #include <gmp.h>
	import "C"

is a signal to cgo.  The doc comment on the import of "C" provides
additional context for the C file.  Here it is just a single #include
but it could contain arbitrary C definitions to be imported and used.

Cgo recognizes any use of a qualified identifier C.xxx and uses gcc to
find the definition of xxx.  If xxx is a type, cgo replaces C.xxx with
a Go translation.  C arithmetic types translate to precisely-sized Go

<div class="termy">

```console
$ pip install jinja2

---> 100%
```

</div>

## Usando `Jinja2Templates` { #using-jinja2templates }

* Importe `Jinja2Templates`.
* Crie um objeto `templates` que você possa reutilizar posteriormente.
* Declare um parâmetro `Request` no *path operation* que retornará um template.

    this.keyTable = keyTable;
    this.valueTable = valueTable;
    this.entries = entries;
    this.mask = mask;
    this.hashCode = hashCode;
  }

  // checkNoConflictInKeyBucket is static imported from RegularImmutableMap

  /**
   * @throws IllegalArgumentException if another entry in the bucket has the same key
   * @throws BucketOverflowException if this bucket has too many entries, which may indicate a hash

///

## Execute o Programa Servidor { #run-the-server-program }

Se você instalou um servidor ASGI manualmente, normalmente precisará passar uma string de importação em um formato especial para que ele importe sua aplicação FastAPI:

<div class="termy">

```console
$ uvicorn main:app --host 0.0.0.0 --port 80

<span style="color: green;">INFO</span>:     Uvicorn running on http://0.0.0.0:80 (Press CTRL+C to quit)

E seus usuários poderiam fazer login tanto pela sua aplicação Django quanto pela sua aplicação **FastAPI**, ao mesmo tempo.

///

## Criar o hash e verificar as senhas { #hash-and-verify-the-passwords }

Importe as ferramentas que nós precisamos de `pwdlib`.

Crie uma instância de PasswordHash com as configurações recomendadas – ela será usada para criar o hash e verificar as senhas.

/// tip | Dica