Remember that when you import `Query`, `Path`, and others from `fastapi`, those are actually functions that return special classes.

///

/// tip

Notice how each model's attribute with a type, default value and `Field` has the same structure as a *path operation function's* parameter, with `Field` instead of `Path`, `Query` and `Body`.

///

## Add extra information { #add-extra-information }

(e)||1!==e.nodeType)throw new Error('Invalid "target" value, use a valid Element');if("copy"===n&&e.hasAttribute("disabled"))throw new Error('Invalid "target" attribute. Please use "readonly" instead of "disabled" attribute');if("cut"===n&&(e.hasAttribute("readonly")||e.hasAttribute("disabled")))throw new Error('Invalid "target" attribute. You can\'t cut text from elements with "readonly" or "disabled" attributes')}return t?f(t,{container:o}):e?"cut"===n?a(e):f(e,{container:o}):void 0};function ...

    // ===================================================================================
    //                                                                           Attribute
    //                                                                           =========
    /** boost */
    protected Float boost;

    /** createdBy */
    protected String createdBy;

    /** createdTime */

public class BsWebConfigCB extends EsAbstractConditionBean {

    // ===================================================================================
    //                                                                           Attribute
    //                                                                           =========
    protected BsWebConfigCQ _conditionQuery;
    protected BsWebConfigCA _conditionAggregation;

    private static final long serialVersionUID = 1L;

    // ===================================================================================
    //                                                                           Attribute
    //                                                                           =========
    protected DocMeta docMeta;
    protected final EntityUniqueDrivenProperties __uniqueDrivenProperties = newUniqueDrivenProperties();

    /**
     * Both <code>FILE_NOTIFY_CHANGE_FILE_NAME</code> and <code>FILE_NOTIFY_CHANGE_DIR_NAME</code>
     */
    int FILE_NOTIFY_CHANGE_NAME = 0x00000003;

    /**
     * Any attribute change in the watched directory or subtree causes a change notification wait operation to return.
     */
    int FILE_NOTIFY_CHANGE_ATTRIBUTES = 0x00000004;

    /**

    // ===================================================================================
    //                                                                           Attribute
    //                                                                           =========
    @Resource
    private UserService userService;
    @Resource
    private RoleService roleService;
    @Resource

Now use the parameter `callbacks` in *your API's path operation decorator* to pass the attribute `.routes` (that's actually just a `list` of routes/*path operations*) from that callback router:

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[33] *}

/// tip

Notice that you are not passing the router itself (`invoices_callback_router`) to `callback=`, but the attribute `.routes`, as in `invoices_callback_router.routes`.

///

You can reuse FastAPI's internal functions to create the HTML pages for the docs, and pass them the needed arguments:

* `openapi_url`: the URL where the HTML page for the docs can get the OpenAPI schema for your API. You can use here the attribute `app.openapi_url`.
* `title`: the title of your API.
* `oauth2_redirect_url`: you can use `app.swagger_ui_oauth2_redirect_url` here to use the default.

    private final FessUser user;

    // ===================================================================================
    //                                                                           Attribute
    //                                                                           =========

    // ===================================================================================