Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

///

/// note

This is supported since FastAPI version `0.113.0`. 🤓

///

## Pydantic Models for Forms { #pydantic-models-for-forms }

* `allow_origins` - Список источников, на которые разрешено выполнять кросс-доменные запросы. Например, `['https://example.org', 'https://www.example.org']`. Можно использовать `['*']`, чтобы разрешить любые источники.
* `allow_origin_regex` - Регулярное выражение для определения  источников, на которые разрешено выполнять кросс-доменные запросы. Например, `'https://.*\.example\.org'`.

///

{* ../../docs_src/extra_models/tutorial003.py hl[1,14:15,18:20,33] *}

### `Union` no Python 3.10

Neste exemplo, passamos `Union[PlaneItem, CarItem]` como o valor do argumento `response_model`.

        String[] sitemaps = new String[] { "http://example.com/sitemap.xml", "http://test.com/sitemap.xml" };
        crawlerContext.addSitemaps(sitemaps);

        // Remove and verify
        String[] removedSitemaps = crawlerContext.removeSitemaps();
        assertNotNull(removedSitemaps);
        assertEquals(2, removedSitemaps.length);
        assertEquals("http://example.com/sitemap.xml", removedSitemaps[0]);

    "tax": 3.2,
    "tags": [
        "rock",
        "metal",
        "bar"
    ],
    "images": [
        {
            "url": "http://example.com/baz.jpg",
            "name": "The Foo live"
        },
        {
            "url": "http://example.com/dave.jpg",
            "name": "The Baz"
        }
    ]
}
```

/// info | informação

### Docs for tests

Most of the tests actually run against the example source files in the documentation.

This helps to make sure that:

* The documentation is up-to-date.
* The documentation examples can be run as is.
* Most of the features are covered by the documentation, ensured by test coverage.

#### Apps and docs at the same time

If you run the examples with, e.g.:

<div class="termy">

```console

* `allow_origins` - Список джерел, яким дозволено здійснювати міждоменні запити.  Наприклад `['https://example.org', 'https://www.example.org']`. Ви можете використовувати ['*'], щоб дозволити всі джерела.
* `allow_origin_regex` - Рядок регулярного виразу для відповідності джерелам, яким дозволено здійснювати міждоменні запити. Наприклад, `'https://.*\.example\.org'`.

 * shared resources.
 *
 * @param <K> the most general type of keys this listener can listen for; for example {@code Object}
 *     if any key is acceptable
 * @param <V> the most general type of values this listener can listen for; for example {@code
 *     Object} if any key is acceptable
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible
public interface RemovalListener<K, V> {

 *
 * @since 4.0.0
 */
@Experimental
@Consumer
public interface VersionResolver extends Service {

    /**
     * Resolves an artifact's meta version (if any) to a concrete version.
     * For example, resolves "1.0-SNAPSHOT" to "1.0-20090208.132618-23".
     *
     * @param session The repository session, must not be {@code null}.

////

## Read env vars in Python { #read-env-vars-in-python }

You could also create environment variables **outside** of Python, in the terminal (or with any other method), and then **read them in Python**.

For example you could have a file `main.py` with:

```Python hl_lines="3"
import os

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

/// tip