* There's a subdirectory `app/routers/` with another file `__init__.py`, so it's a "Python subpackage": `app.routers`.
* The file `app/routers/items.py` is inside a package, `app/routers/`, so, it's a submodule: `app.routers.items`.
* The same with `app/routers/users.py`, it's another submodule: `app.routers.users`.

[providers]
  [providers.file]
    filename = "routes.toml"
```

This tells Traefik to listen on port 9999 and to use another file `routes.toml`.

/// tip

We are using port 9999 instead of the standard HTTP port 80 so that you don't have to run it with admin (`sudo`) privileges.

///

Now create that other file `routes.toml`:

```TOML hl_lines="5  12  20"
[http]
  [http.middlewares]

* `dependencies`: to include ✨ router-level dependencies ✨ that apply to all the *path operations* in a router. Up to now, this was only possible with `include_router`.
* `callbacks`: OpenAPI callbacks that apply to all the *path operations* in this router.
* `deprecated`: to mark all the *path operations* in a router as deprecated.

func registerAPIFunctions(muxRouter *mux.Router, objLayer ObjectLayer, apiFunctions ...string) {
	if len(apiFunctions) == 0 {
		// Register all api endpoints by default.
		registerAPIRouter(muxRouter)
		return
	}
	// API Router.
	apiRouter := muxRouter.PathPrefix(SlashSeparator).Subrouter()
	// Bucket router.

///

### Add the callback router { #add-the-callback-router }

At this point you have the *callback path operation(s)* needed (the one(s) that the *external developer*  should implement in the *external API*) in the callback router you created above.

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/custom_request_and_route/tutorial002.py hl[16:18] *}

## Custom `APIRoute` class in a router { #custom-apiroute-class-in-a-router }

You can also set the `route_class` parameter of an `APIRouter`:

{* ../../docs_src/custom_request_and_route/tutorial003.py hl[26] *}

* `summary`: A short summary of the API.
* `description`: The description of your API, this can include markdown and will be shown in the docs.
* `routes`: A list of routes, these are each of the registered *path operations*. They are taken from `app.routes`.

/// info

The parameter `summary` is available in OpenAPI 3.1.0 and above, supported by FastAPI 0.99.0 and above.

///

)

// adminErasureTestBed - encapsulates subsystems that need to be setup for
// admin-handler unit tests.
type adminErasureTestBed struct {
	erasureDirs []string
	objLayer    ObjectLayer
	router      *mux.Router
	done        context.CancelFunc
}

// prepareAdminErasureTestBed - helper function that setups a single-node
// Erasure backend for admin-handler tests.

type stsAPIHandlers struct{}

// registerSTSRouter - registers AWS STS compatible APIs.
func registerSTSRouter(router *mux.Router) {
	// Initialize STS.
	sts := &stsAPIHandlers{}

	// STS Router
	stsRouter := router.NewRoute().PathPrefix(SlashSeparator).Subrouter()

	// Assume roles with no JWT, handles AssumeRole.

        logger.resetStatistics();

        Map<EventType, Long> statsAfter = logger.getStatistics();
        // After reset, all counters should be 0
        for (Long count : statsAfter.values()) {
            assertEquals(Long.valueOf(0), count, "All statistics should be 0 after reset");
        }
    }

    @Test