If something seems interesting and useful to your project, go ahead and check it, but otherwise, you might probably just skip them.

/// tip

If you want to **learn FastAPI** in a structured way (recommended), go and read the [Tutorial - User Guide](../tutorial/index.md) chapter by chapter instead.

There are several custom response classes you can use to create an instance and return them directly from your *path operations*.

Read more about it in the [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).

You can import them directly from `fastapi.responses`:

```python
from fastapi.responses import (
    FileResponse,
    HTMLResponse,

For example, if an attacker were to upload a malicious video file, they could
potentially exploit a vulnerability in the TensorFlow code that handles videos,
which could allow them to execute arbitrary code on the system running
TensorFlow.

It is important to keep TensorFlow up to date with the latest security patches
and follow the sandboxing guideline above to protect against these types of
vulnerabilities.

You can also declare the `Response` parameter in dependencies, and set headers (and cookies) in them.

## Return a `Response` directly { #return-a-response-directly }

You can also add headers when you return a `Response` directly.

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 *

But you still need to define what is the dependable, the callable that you pass as a parameter to `Depends()` or `Security()`.

There are multiple tools that you can use to create those dependables, and they get integrated into OpenAPI so they are shown in the automatic docs UI, they can be used by automatically generated clients and SDKs, etc.

You can import them from `fastapi.security`:

```python

# Repository Management

Here's a short description of how the FastAPI repository is managed and maintained.

## Owner

I, [@tiangolo](https://github.com/tiangolo), am the creator and owner of the FastAPI repository. 🤓

I normally give the final review to each PR before merging them. I make the final decisions on the project, I'm the [<abbr title="Benevolent Dictator For Life">BDFL</abbr>](https://en.wikipedia.org/wiki/Benevolent_dictator_for_life). 😅

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * 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,

- ⚡ [**FastAPI**](https://fastapi.tiangolo.com) for the Python backend API.
  - 🧰 [SQLModel](https://sqlmodel.tiangolo.com) for the Python SQL database interactions (ORM).
  - 🔍 [Pydantic](https://docs.pydantic.dev), used by FastAPI, for the data validation and settings management.
  - 💾 [PostgreSQL](https://www.postgresql.org) as the SQL database.
- 🚀 [React](https://react.dev) for the frontend.

* `title`: the title of your API.
* `oauth2_redirect_url`: you can use `app.swagger_ui_oauth2_redirect_url` here to use the default.
* `swagger_js_url`: the URL where the HTML for your Swagger UI docs can get the **JavaScript** file. This is the custom CDN URL.