```Python hl_lines="11  13-14"
{!> ../../docs_src/response_model/tutorial004.py!}
```

////

* `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.

///

## 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.

### Override request validation exceptions

  /** Hostname, IPv4/IPv6 literal, or unvalidated nonsense. */
  private final String host;

  /** Validated port number in the range [0..65535], or NO_PORT */
  private final int port;

  /** True if the parsed host has colons, but no surrounding brackets. */
  private final boolean hasBracketlessColons;

  private HostAndPort(String host, int port, boolean hasBracketlessColons) {
    this.host = host;
    this.port = port;

			<li class="nav-item has-treeview <c:if test="${param.menuCategoryType=='system'}">menu-open</c:if>">
				<a href="#" class="nav-link <c:if test="${param.menuCategoryType=='system'}">active</c:if>">
					<em class='nav-icon fa fa-laptop'>
					<p>

              try {
                if (state() != State.STOPPING) {
                  // This means that the state has changed since we were scheduled. This implies
                  // that an execution of runOneIteration has thrown an exception and we have
                  // transitioned to a failed state, also this means that shutDown has already
                  // been called, so we do not want to call it again.
                  return;

                  x-kubernetes-validations:
                  - message: Address is required
                    rule: has(self.address) || has(self.network)
                  - message: UDS may not include ports
                    rule: '(has(self.address) && self.address.startsWith(''unix://''))
                      ? !has(self.ports) : true'
                maxItems: 4096
                type: array
              exportTo:

Now if you generate the client again, you will see that it has the improved method names:

<img src="/img/tutorial/generate-clients/image07.png">

As you see, the method names now have the tag and then the function name, now they don't include information from the URL path and the HTTP operation.

### Preprocess the OpenAPI Specification for the Client Generator

The generated code still has some **duplicated information**.

.isValid&&e&&i.validateOnKeyUp(c,d),this},a.fn.validateOnKeyUp=function(b,c){return this.each(function(){var d=a(this);d.valAttr("has-keyup-event")||d.valAttr("has-keyup-event","true").bind("keyup.validation",function(a){9!==a.keyCode&&d.validateInputOnBlur(b,c,!1,"keyup")})}),this},a.fn.removeKeyUpValidation=function(){return this.each(function(){a(this).valAttr("has-keyup-event",!1).unbind("keyup.validation")}),this},a.fn.valAttr=function(a,b){return b===c?this.attr("data-validation-"+a):b===!...

- es-image has been updated to Elasticsearch 6.7.2. ([#77765](https://github.com/kubernetes/kubernetes/pull/77765))
- metrics-server has been updated to v0.3.3. ([#77950](https://github.com/kubernetes/kubernetes/pull/77950))
- ip-masq-agent has been updated to v2.4.1. ([#77844](https://github.com/kubernetes/kubernetes/pull/77844))
- addon-manager has been updated to v9.0.1 ([#77282](https://github.com/kubernetes/kubernetes/pull/77282))

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.