{* ../../docs_src/header_param_models/tutorial002_an_py310.py hl[10] *}

If a client tries to send some **extra headers**, they will receive an **error** response.

For example, if the client tries to send a `tool` header with a value of `plumbus`, they will receive an **error** response telling them that the header parameter `tool` is not allowed:

```json
{
    "detail": [
        {
            "type": "extra_forbidden",

	globalConfigDir = defaultConfigDir
	// Points to current certs directory set by user with --certs-dir
	globalCertsDir = defaultCertsDir
	// Points to relative path to certs directory and is <value-of-certs-dir>/CAs
	globalCertsCADir = defaultCertsCADir
)

// Get - returns current directory.
func (dir *ConfigDir) Get() string {
	return dir.path
}

//
// You can use returned dial function for `http.Transport.DialContext`.
//
// In this function, it uses functions from `rand` package. To make it really random,
// you MUST call `rand.Seed` and change the value from the default in your application
func DialContextWithLookupHost(lookupHost LookupHost, baseDialCtx DialContext) DialContext {
	if lookupHost == nil {
		lookupHost = net.DefaultResolver.LookupHost
	}

	// Handle migration from lockEnabled to newer format.
	if b.LockEnabled {
		configs[objectLockConfig] = enabledBucketObjectLockConfig
		b.LockEnabled = false // legacy value unset it
		// we are only interested in b.ObjectLockConfigXML or objectLockConfig value
	}

	for _, legacyFile := range legacyConfigs {
		configFile := path.Join(bucketMetaPrefix, b.Name, legacyFile)

     * <p>Then the returned value is {@code groupId:artifactId} when there is a name clash and
     * {@code :artifactId} if there is no conflict.
     * This method is made package-private for testing purposes.
     *
     * @param mavenProjects Maven projects which are part of build execution.
     * @param firstFailedProject The first project which has failed.

    }

    private
    fun store(properties: Properties) {
        PropertiesUtils.store(
            properties, libraryVersionFile.get().asFile,
            "Generated file, please do not edit - Version values used in build-init templates",
            Charsets.ISO_8859_1, "\n"
        )
    }

    private
    fun findLatest(name: String, notation: String, dest: Properties) {

                    return Collections.unmodifiableList(new ArrayList<>(delegate.getMojoDescriptor()
                            .getPluginDescriptor()
                            .getLifecycleMappings()
                            .values()));
                } catch (Exception e) {
                    throw new RuntimeException("Unable to load plugin lifecycles", e);
                }
            }

            @Override

Então você pode escrever um template em `templates/item.html`, por exemplo:

```jinja hl_lines="7"
{!../../docs_src/templates/templates/item.html!}
```

### Valores de contexto do template { #template-context-values }

No código HTML que contém:

{% raw %}

```jinja
Item ID: {{ id }}
```

{% endraw %}

...aparecerá o `id` obtido do "context" `dict` que você passou:

```Python
{"id": id}
```

                if (retValue.length() >= 2 && (retValue.charAt(1) == '|' || retValue.charAt(1) == ':')) {
                    // special case: if there is a windows drive letter, then keep the original return value
                    retValue = retValue.charAt(0) + ":" + retValue.substring(2);
                } else {
                    // Now we expect the host
                    int index = retValue.indexOf('/');

When you create a **FastAPI** *path operation* you can normally return any data from it: a `dict`, a `list`, a Pydantic model, a database model, etc.

By default, **FastAPI** would automatically convert that return value to JSON using the `jsonable_encoder` explained in [JSON Compatible Encoder](../tutorial/encoder.md){.internal-link target=_blank}.