public static final String THREADS = "T";
        public static final String BUILDER = "b";
        public static final String NO_TRANSFER_PROGRESS = "ntp";
        public static final String CACHE_ARTIFACT_NOT_FOUND = "canf";
        public static final String STRICT_ARTIFACT_DESCRIPTOR_POLICY = "sadp";
        public static final String IGNORE_TRANSITIVE_REPOSITORIES = "itr";
        public static final String AT_FILE = "af";

    public static final String BUILDER = "b";

    public static final String NO_TRANSFER_PROGRESS = "ntp";

    public static final String COLOR = "color";

    public static final String CACHE_ARTIFACT_NOT_FOUND = "canf";

    public static final String STRICT_ARTIFACT_DESCRIPTOR_POLICY = "sadp";

    public static final String IGNORE_TRANSITIVE_REPOSITORIES = "itr";

    public static final String DEBUG = "debug";

 |                 users on a machine (assuming they're all using the same Maven
 |                 installation). It's normally provided in
 |                 ${maven.installation.conf}/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -is /path/to/installation/settings.xml
 |
 | The sections in this sample file are intended to give you a running start at

        FileSystem fs = Jimfs.newFileSystem(Configuration.windows());

        Path mavenHome = fs.getPath("C:\\maven");
        Files.createDirectories(mavenHome);
        Path mavenConf = mavenHome.resolve("conf");
        Files.createDirectories(mavenConf);
        Path mavenUserProps = mavenConf.resolve("maven-user.properties");

    /** Array of fields that can be highlighted in search results */
    protected String[] highlightedFields;

    /** Array of fields that can be searched against */
    protected String[] searchFields;

    /** Set of fields that can be searched against for O(1) lookup */
    protected Set<String> searchFieldSet;

    /** Array of fields that can be used for faceted search */
    protected String[] facetFields;

So, you can look for that specific exception inside the dependency with `except SomeException`.

In the same way, you can use `finally` to make sure the exit steps are executed, no matter if there was an exception or not.

{* ../../docs_src/dependencies/tutorial007_py39.py hl[3,5] *}

## Sub-dependencies with `yield` { #sub-dependencies-with-yield }

{* ../../docs_src/query_params_str_validations/tutorial006_an_py39.py hl[9] *}

### Required, can be `None` { #required-can-be-none }

You can declare that a parameter can accept `None`, but that it's still required. This would force clients to send a value, even if the value is `None`.

If there is no discussion for that language, you can start by requesting the new language. For that, you can follow these steps:

* Create a new discussion following the template.
* Get a few native speakers to comment on the discussion and commit to help review translations for that language.

Once there are several people in the discussion, the FastAPI team can evaluate it and can make it an official translation.

# Response Model - Return Type { #response-model-return-type }

You can declare the type used for the response by annotating the *path operation function* **return type**.

You can use **type annotations** the same way you would for input data in function **parameters**, you can use Pydantic models, lists, dictionaries, scalar values like integers, booleans, etc.

{* ../../docs_src/response_model/tutorial001_01_py310.py hl[16,21] *}

#### Union { #union }

You can declare that a variable can be any of **several types**, for example, an `int` or a `str`.

In Python 3.6 and above (including Python 3.10) you can use the `Union` type from `typing` and put inside the square brackets the possible types to accept.