*    will be used to authenticate the client's certificate chain. Typically this is not the same
 *    set of root certificates used in server authentication. Instead it will be a small set of
 *    roots private to an organization or service.
 */
class HandshakeCertificates private constructor(
  @get:JvmName("keyManager") val keyManager: X509KeyManager,

**FastAPI** provides several tools to help you deal with **Security** easily, rapidly, in a standard way, without having to study and learn all the security specifications.

But first, let's check some small concepts.

## In a hurry?

If you don't care about any of these terms and you just need to add security with authentication based on username and password *right now*, skip to the next chapters.

## OAuth2

Depending on your use case, you might prefer to use a different library, but if you asked me, I would probably suggest you try **Strawberry**.

Here's a small preview of how you could integrate Strawberry with FastAPI:

```Python hl_lines="3  22  25-26"
{!../../../docs_src/graphql/tutorial001.py!}
```

  return result.toTypedArray()
}

/**
 * Returns true if there is an element in this array that is also in [other]. This method terminates
 * if any intersection is found. The sizes of both arguments are assumed to be so small, and the
 * likelihood of an intersection so great, that it is not worth the CPU cost of sorting or the
 * memory cost of hashing.
 */
internal fun Array<String>.hasIntersection(
  other: Array<String>?,

  // The token will only be valid for as long as the bound object exists.
  // NOTE: The API server's TokenReview endpoint will validate the
  // BoundObjectRef, but other audiences may not. Keep ExpirationSeconds
  // small if you want prompt revocation.
  // +optional
  optional BoundObjectReference boundObjectRef = 3;
}

// TokenRequestStatus is the result of a token request.
message TokenRequestStatus {

But if you need to access variables and objects from the same **FastAPI** app, or you need to perform small background tasks (like sending an email notification), you can simply just use `BackgroundTasks`.

## Recap

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.internal.idn

import okio.BufferedSink

/**
 * An IDNA mapping table optimized for small code and data size.
 *
 * Code Points in Sections
 * =======================
 *
 * The full range of code points is 0..0x10fffe. We can represent any of these code points with 21
 * bits.
 *

   1. Definitions.

      "License" shall mean the terms and conditions for use, reproduction,
      and distribution as defined by Sections 1 through 9 of this document.

      "Licensor" shall mean the copyright owner or entity authorized by
      the copyright owner that is granting the License.

      "Legal Entity" shall mean the union of the acting entity and all

And all of them (or any portion of them that you want) can take the advantage of re-using these dependencies or any other dependencies you create.

And all these thousands of *path operations* can be as small as 3 lines:

=== "Python 3.10+"

    ```Python hl_lines="30-32"
    {!> ../../../docs_src/security/tutorial002_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="30-32"

Keep in mind that this means that the whole contents will be stored in memory. This will work well for small files.

But there are several cases in which you might benefit from using `UploadFile`.

## File Parameters with `UploadFile`

Define a file parameter with a type of `UploadFile`:

=== "Python 3.9+"