* Give you the received data in the parameter `item`.
    * As you declared it in the function to be of type `Item`, you will also have all the editor support (completion, etc) for all of the attributes and their types.
* Generate <a href="https://json-schema.org" class="external-link" target="_blank">JSON Schema</a> definitions for your model, you can also use them anywhere else you like if it makes sense for your project.

    And many teams use only `PUT`, even for partial updates.

    You are **free** to use them however you want, **FastAPI** doesn't impose any restrictions.

    But this guide shows you, more or less, how they are intended to be used.

### Using Pydantic's `exclude_unset` parameter

If you want to receive partial updates, it's very useful to use the parameter `exclude_unset` in Pydantic's model's `.model_dump()`.

You can see more details in <a href="https://www.starlette.io/background/" class="external-link" target="_blank">Starlette's official docs for Background Tasks</a>.

## Caveat

You pay. 💸

The cashier gives you the number of your turn.

<img src="/img/async/concurrent-burgers/concurrent-burgers-04.png" class="illustration">

While you are waiting, you go with your crush and pick a table, you sit and talk with your crush for a long time (as your burgers are very fancy and take some time to prepare).

object browser built into MinIO Server. Point a web browser running on the host machine to <http://127.0.0.1:9000> and log in with the
root credentials. You can use the Browser to create buckets, upload objects, and browse the contents of the MinIO server.

/*
 * Copyright (C) 2011 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the
 * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either

    In Pydantic version 1, you would use an internal class `Config` and `schema_extra`, as described in <a href="https://docs.pydantic.dev/1.10/usage/schema/#schema-customization" class="external-link" target="_blank">Pydantic's docs: Schema customization</a>.

    You can set `schema_extra` with a `dict` containing any additional data you would like to show up in the generated JSON Schema, including `examples`.

!!! tip

This gives you a lot of flexibility. You can return any data type, override any data declaration or validation, etc.

## Using the `jsonable_encoder` in a `Response`

Because **FastAPI** doesn't do any change to a `Response` you return, you have to make sure it's contents are ready for it.

## Use a `Response` parameter

You can declare a parameter of type `Response` in your *path operation function* (as you can do for cookies).

And then you can set headers in that *temporal* response object.

```Python hl_lines="1  7-8"
{!../../../docs_src/response_headers/tutorial002.py!}
```

And then you can return any object you need, as you normally would (a `dict`, a database model, etc).

## **FastAPI** utilities

FastAPI provides several tools for each of these security schemes in the `fastapi.security` module that simplify using these security mechanisms.

In the next chapters you will see how to add security to your API using those tools provided by **FastAPI**.