/settings.gradle*                           @gradle/bt-developer-productivity
gradle/shared-with-buildSrc/                @gradle/bt-developer-productivity
platforms/build-infrastructure/             @gradle/bt-developer-productivity
subprojects/internal-build-reports/         @gradle/bt-developer-productivity
testing/internal-architecture-testing/      @gradle/bt-developer-productivity

  /**
   * The HTTP <a
   * href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Link_prefetching_FAQ#As_a_server_admin.2C_can_I_distinguish_prefetch_requests_from_normal_requests.3F">{@code
   * Purpose}</a> header field name.
   *
   * @since 28.0
   */
  public static final String PURPOSE = "Purpose";
  /**
   * The HTTP <a

Ostatnia ankieta <abbr title="coroczna ankieta przeprowadza w środowisku programistów języka Python">Python developer survey</abbr> jasno wskazuje, że <a href="https://www.jetbrains.com/research/python-developers-survey-2017/#tools-and-features" class="external-link" target="_blank">najczęściej używaną funkcjonalnością jest autouzupełnianie w edytorze</a>.

**FastAPI** has a very powerful but intuitive **<abbr title="also known as components, resources, providers, services, injectables">Dependency Injection</abbr>** system.

It is designed to be very simple to use, and to make it very easy for any developer to integrate other components with **FastAPI**.

## What is "Dependency Injection"

* **Fast to code**: Increase the speed to develop features by about 200% to 300%. *
* **Fewer bugs**: Reduce about 40% of human (developer) induced errors. *
* **Intuitive**: Great editor support. <abbr title="also known as auto-complete, autocompletion, IntelliSense">Completion</abbr> everywhere. Less time debugging.

!!! note "Technical Details"
    You could also use `from starlette.responses import HTMLResponse`.

    **FastAPI** provides the same `starlette.responses` as `fastapi.responses` just as a convenience for you, the developer. But most of the available responses come directly from Starlette.

### `Response`

The main `Response` class, all the other responses inherit from it.

You can return it directly.

```JSON
{
  "username": "johndoe",
  "email": "******@****.***",
  "full_name": "John Doe",
  "disabled": false
}
```

<img src="/img/tutorial/security/image09.png">

If you open the developer tools, you could see how the data sent only includes the token, the password is only sent in the first request to authenticate the user and get that access token, but not afterwards:

<img src="/img/tutorial/security/image10.png">

* **Fast to code**: Increase the speed to develop features by about 200% to 300%. *
* **Fewer bugs**: Reduce about 40% of human (developer) induced errors. *
* **Intuitive**: Great editor support. <abbr title="also known as auto-complete, autocompletion, IntelliSense">Completion</abbr> everywhere. Less time debugging.

	if err.HTTPStatusCode == http.StatusServiceUnavailable {
		// Set retry-after header to indicate user-agents to retry request after 120secs.
		// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After
		w.Header().Set(xhttp.RetryAfter, "120")
	}

	switch err.Code {
	case "InvalidRegion":

Later you will see how **powerful** it can be.

!!! tip
    The fact that this is **standard Python** means that you will still get the **best possible developer experience** in your editor, with the tools you use to analyze and refactor your code, etc. ✨

    And also that your code will be very compatible with many other Python tools and libraries. 🚀

## Type hints in **FastAPI**