{* ../../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: `[]`.

but you might want to omit them from the result if they were not actually stored.

func testAPIHeadObjectHandler(obj ObjectLayer, instanceType, bucketName string, apiRouter http.Handler,
	credentials auth.Credentials, t *testing.T,
) {
	objectName := "test-object"
	// set of byte data for PutObject.
	// object has to be created before running tests for HeadObject.
	// this is required even to assert the HeadObject data,
	// since dataInserted === dataFetched back is a primary criteria for any object storage this assertion is critical.

    OkHttp 2 the built-in disk cache is the only supported response cache.

 *  **HttpResponseCache has been renamed to Cache.** Install it with
    `OkHttpClient.setCache(...)` instead of `OkHttpClient.setResponseCache(...)`.

 *  **OkAuthenticator has been replaced with Authenticator.** This new
    authenticator has access to the full incoming response and can respond with

///

## Override the default exception handlers { #override-the-default-exception-handlers }

**FastAPI** has some default exception handlers.

These handlers are in charge of returning the default JSON responses when you `raise` an `HTTPException` and when the request has invalid data.

You can override these exception handlers with your own.

   * value for which {@link Comparable#compareTo(Object)} never returns a positive value for any
   * input of type {@code C}.
   *
   * <p>The default implementation throws {@code NoSuchElementException}.
   *
   * @return the minimum value of type {@code C}; never null
   * @throws NoSuchElementException if the type has no (practical) minimum value; for example,

The main constraint to consider is that there has to be a **single** component handling the **port** in the **public IP**. And then it has to have a way to **transmit** the communication to the replicated **processes/workers**.

Here are some possible combinations and strategies:

* **Uvicorn** with `--workers`

* For `PUT` requests to `/items/{item_id}`, read the body as JSON:
    * Check that it has a required attribute `name` that should be a `str`.
    * Check that it has a required attribute `price` that has to be a `float`.
    * Check that it has an optional attribute `is_offer`, that should be a `bool`, if present.
    * All this would also work for deeply nested JSON objects.

   *
   * @return true if the Bloom filter's bits changed as a result of this operation. If the bits
   *     changed, this is <i>definitely</i> the first time {@code object} has been added to the
   *     filter. If the bits haven't changed, this <i>might</i> be the first time {@code object} has
   *     been added to the filter. Note that {@code put(t)} always returns the <i>opposite</i>

    for details.

    The summary is that it ignores one file in favor of the other.
    util.concurrent, like nearly all our packages, has two .gwt.xml files: one
    for prod and one for tests. However, unlike our other packages, as of this
    writing it has test supersource but no prod supersource.

    GWT happens to use the prod .gwt.xml, so it looks for no supersource for

     *
     * @return whether the share is in DFS
     */
    boolean isShareDfs();

    /**
     * Indicates whether the tree connection has been successfully established and has a valid tree ID.
     *
     * @return whether the tree id is a valid one
     */
    boolean isValidTid();