cli_main = None  # type: ignore


def main() -> None:
    if not cli_main:  # type: ignore[truthy-function]
        message = 'To use the fastapi command, please install "fastapi[standard]":\n\n\tpip install "fastapi[standard]"\n'
        print(message)
        raise RuntimeError(message)  # noqa: B904

## Dependências { #dependencies }

O FastAPI depende do Pydantic e do Starlette.

### Dependências `standard` { #standard-dependencies }

Quando você instala o FastAPI com `pip install "fastapi[standard]"`, ele vêm com o grupo `standard` (padrão) de dependências opcionais:

Utilizado pelo Pydantic:

In diesem Fall können Sie einfach die Standard-`dataclasses` durch `pydantic.dataclasses` ersetzen, was einen direkten Ersatz darstellt:

{* ../../docs_src/dataclasses_/tutorial003_py310.py hl[1,4,7:10,13:16,22:24,27] *}

1. Wir importieren `field` weiterhin von Standard-`dataclasses`.

2. `pydantic.dataclasses` ist ein direkter Ersatz für `dataclasses`.

In that case, you can simply swap the standard `dataclasses` with `pydantic.dataclasses`, which is a drop-in replacement:

{* ../../docs_src/dataclasses_/tutorial003_py310.py hl[1,4,7:10,13:16,22:24,27] *}

1. We still import `field` from standard `dataclasses`.

2. `pydantic.dataclasses` is a drop-in replacement for `dataclasses`.

    /**
     * Inject a standard <code>Maven</code> logging mechanism to allow this <code>Mojo</code> to communicate events
     * and feedback to the user.
     *
     * @param log a new logger
     *
     * @deprecated Use SLF4J directly
     */
    @Deprecated
    void setLog(Log log);

    /**
     * Furnish access to the standard Maven logging mechanism which is managed in this base class.

        * The generated schema will specify that the `set` values are unique (using JSON Schema's `uniqueItems`).
* `bytes`:
    * Standard Python `bytes`.
    * In requests and responses will be treated as `str`.
    * The generated schema will specify that it's a `str` with `binary` "format".
* `Decimal`:
    * Standard Python `Decimal`.
    * In requests and responses, handled the same as a `float`.

package cmd

import "net/http"

// Standard cross domain policy information located at https://s3.amazonaws.com/crossdomain.xml
const crossDomainXML = `<?xml version="1.0"?><!DOCTYPE cross-domain-policy SYSTEM "http://www.adobe.com/xml/dtds/cross-domain-policy.dtd"><cross-domain-policy><allow-access-from domain="*" secure="false" /></cross-domain-policy>`

// Standard path where an app would find cross domain policy information.

 * - The target JVM version
 * - Workarounds which may affect the way the compilation is performed
 *
 * The compilation workarounds include:
 * - Using JDK internal classes
 * - Using Java standard library APIs that were introduced after the JVM version they are targeting
 *
 * All of these workarounds should be generally avoided, but, with this data we can configure the
 * compile tasks to permit some of these requirements.

copies of a package at different versions if the package is
imported normally and vendored by the standard library.

Vendored packages are internally renamed with a "vendor/" prefix
to preserve the invariant that all packages have distinct paths.
This is necessary to avoid compiler and linker conflicts. Adding
a "vendor/" prefix also maintains the invariant that standard
library packages begin with a dotless path element.

Например, чтобы установить Uvicorn:

<div class="termy">

```console
$ pip install "uvicorn[standard]"

---> 100%
```

</div>

Аналогично устанавливаются и другие ASGI‑серверы.

/// tip | Совет

С добавлением `standard` Uvicorn установит и будет использовать ряд рекомендованных дополнительных зависимостей.