Your response model could have default values, like:

{* ../../docs_src/response_model/tutorial004_py310.py hl[9,11:12] *}

* `description: Union[str, None] = None` (or `str | None = None` in Python 3.10) has a default of `None`.
* `tax: float = 10.5` has a default of `10.5`.
* `tags: List[str] = []` has a default of an empty list: `[]`.

app_nested = FastAPI(strict_content_type=False)  # lax app
outer_router = APIRouter(prefix="/outer")  # inherits lax from app
inner_strict = APIRouter(prefix="/strict", strict_content_type=True)
inner_default = APIRouter(prefix="/default")


@inner_strict.post("/items/")
async def inner_strict_post(data: dict):
    return data


@inner_default.post("/items/")
async def inner_default_post(data: dict):
    return data

                fConfig.setExcludedDocPaths(getDefaultString("default.config.file.excludedDocPaths", StringUtil.EMPTY));
                fConfig.setExcludedPaths(getDefaultString("default.config.file.excludedPaths", StringUtil.EMPTY));
                fConfig.setIncludedDocPaths(getDefaultString("default.config.file.includedDocPaths", StringUtil.EMPTY));
                fConfig.setIncludedPaths(getDefaultString("default.config.file.includedPaths", StringUtil.EMPTY));

    /**
     * Default constructor for file authentication pager.
     * Creates a new instance with default values.
     */
    public FileAuthPager() {
        // Default constructor
    }

    /** The default number of records to display per page. */
    public static final int DEFAULT_PAGE_SIZE = 20;

    /** The default current page number (1-based). */

    /** Logger instance for this class */
    private static final Logger logger = LogManager.getLogger(PurgeDocJob.class);

    /**
     * Default constructor for PurgeDocJob.
     * Creates a new instance of the document purging job with default settings.
     */
    public PurgeDocJob() {
        // Default constructor
    }

    /**
     * Executes the document purging job.

 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingListMultimap}.
 *
 * @author Kurt Alfred Kluever

 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingSortedSetMultimap}.
 *
 * @author Kurt Alfred Kluever

    /**
     * Retrieve a <code>String</code>. If the key cannot be found,
     * the provided <code>def</code> default parameter will be returned.
     *
     * @param key the property key to look up
     * @param def the default value to return if the property is not found
     * @return the property value, or the default value if not found
     */

    public static String getProperty(final String key, final String def) {

 * DCE/RPC interface for Distributed File System (DFS) operations.
 * Provides structures and methods for DFS management and enumeration.
 */
public class netdfs {

    /**
     * Default constructor for netdfs
     */
    public netdfs() {
        // Default constructor
    }

    /**
     * Gets the DCE/RPC syntax identifier for the DFS interface
     * @return the syntax identifier string
     */

	if animal.Name != "amazing horse" {
		t.Errorf("Update a filed with a default value should occur. But got %v\n", animal.Name)
	}

	// When changing a field with a default value with blank value
	animal.Name = ""
	DB.Save(&animal)
	DB.First(&animal, animal.Counter)
	if animal.Name != "" {
		t.Errorf("Update a filed to blank with a default value should occur. But got %v\n", animal.Name)
	}