enum class Arch(
    val suffix: String,
    val nameOnLinuxWindows: String,
    val nameOnMac: String,
) {
    AMD64("64bit", "amd64", "x86_64"),
    AARCH64("aarch64", "aarch64", "aarch64"),
    ;

    fun asName() = name.lowercase().toCapitalized()
}

enum class Os(
    val agentRequirement: String,
    val androidHome: String,
    val jprofilerHome: String,
    val perfTestWorkingDir: String = "%teamcity.build.checkoutDir%",

///

## Read the Tutorial first { #read-the-tutorial-first }

The next sections assume you already read the main [Tutorial - User Guide: Security](../../tutorial/security/index.md){.internal-link target=_blank}.

/// note

Notice that you have to return the image using a `FileResponse` directly.

///

/// info

Unless you specify a different media type explicitly in your `responses` parameter, FastAPI will assume the response has the same media type as the main response class (default `application/json`).

The same way there is a `Query` and `Path` to define extra data for query and path parameters, **FastAPI** provides an equivalent `Body`.

For example, extending the previous model, you could decide that you want to have another key `importance` in the same body, besides the `item` and `user`.

If you declare it as is, because it is a singular value, **FastAPI** will assume that it is a query parameter.

### Same Schema for Input and Output Models in Docs { #same-schema-for-input-and-output-models-in-docs }

And now there will be one single schema for input and output for the model, only `Item`, and it will have `description` as **not required**:

<div class="screenshot">
<img src="/img/tutorial/separate-openapi-schemas/image05.png">
</div>

### Multiple Applications { #multiple-applications }

In the same server (or servers), there could be **multiple applications**, for example, other API programs or a database.

Only one process can be handling the specific IP and port (the TLS Termination Proxy in our example) but the other applications/processes can be running on the server(s) too, as long as they don't try to use the same **combination of public IP and port**.

Import `BaseSettings` from Pydantic and create a sub-class, very much like with a Pydantic model.

The same way as with Pydantic models, you declare class attributes with type annotations, and possibly default values.

You can use all the same validation features and tools you use for Pydantic models, like different data types and additional validations with `Field()`.

//// tab | Pydantic v2

You could still use most of the features in **FastAPI** with the knowledge from the main [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank}.

Do you want to just have a `str`? Or just a `dict`? Or a database class model instance directly? It all works the same way.

You actually don't have users that log in to your application but robots, bots, or other systems, that have just an access token? Again, it all works the same.

func registerSTSRouter(router *mux.Router) {
	// Initialize STS.
	sts := &stsAPIHandlers{}

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

	// Assume roles with no JWT, handles AssumeRole.
	stsRouter.Methods(http.MethodPost).MatcherFunc(func(r *http.Request, rm *mux.RouteMatch) bool {