*         .put('b', "anana")
   *         .putAll('a', "pple", "sparagus")
   *         .putAll('c', "arrot", "herry")
   *         .build();
   * }
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K, V>
      Collector<T, ?, ImmutableListMultimap<K, V>> toImmutableListMultimap(
          Function<? super T, ? extends K> keyFunction,

   *         .put('b', "anana")
   *         .putAll('a', "pple", "sparagus")
   *         .putAll('c', "arrot", "herry")
   *         .build();
   * }
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <T extends @Nullable Object, K, V>

   *         .put('b', "anana")
   *         .putAll('a', "pple", "sparagus")
   *         .putAll('c', "arrot", "herry")
   *         .build();
   * }
   *
   * @since 21.0
   */
  public static <T extends @Nullable Object, K, V>
      Collector<T, ?, ImmutableSetMultimap<K, V>> toImmutableSetMultimap(
          Function<? super T, ? extends K> keyFunction,

   *         .put('b', "anana")
   *         .putAll('a', "pple", "sparagus")
   *         .putAll('c', "arrot", "herry")
   *         .build();
   * }
   *
   * @since 33.2.0 (available since 21.0 in guava-jre)
   */
  @IgnoreJRERequirement // Users will use this only if they're already using streams.
  public static <T extends @Nullable Object, K, V>

   *     FIRST_LETTER_MULTIMAP.put('a', "pple");
   *     FIRST_LETTER_MULTIMAP.put('a', "sparagus");
   *     FIRST_LETTER_MULTIMAP.put('c', "arrot");
   *     FIRST_LETTER_MULTIMAP.put('c', "herry");
   * }
   * }
   *
   * <p>To collect to an {@link ImmutableMultimap}, use either {@link
   * ImmutableSetMultimap#toImmutableSetMultimap} or {@link
   * ImmutableListMultimap#toImmutableListMultimap}.
   *

   *     FIRST_LETTER_MULTIMAP.put('a', "pple");
   *     FIRST_LETTER_MULTIMAP.put('a', "sparagus");
   *     FIRST_LETTER_MULTIMAP.put('c', "arrot");
   *     FIRST_LETTER_MULTIMAP.put('c', "herry");
   * }
   * }
   *
   * <p>To collect to an {@link ImmutableMultimap}, use either {@link
   * ImmutableSetMultimap#toImmutableSetMultimap} or {@link
   * ImmutableListMultimap#toImmutableListMultimap}.
   *

```mermaid
flowchart LR
    stone(philosophers-stone) -->|requires| harry-1[harry v1]
```

Then, at some point later, you create another project called `prisoner-of-azkaban`, and this project also depends on `harry`, but this project needs **`harry` version `3`**.

```mermaid
flowchart LR

# input the branch name and paste the cherry-pick commit and click Run. A PR
# will be created.

name: Release Branch Cherrypick
on:
  workflow_dispatch:
    inputs:
      # We use this instead of the "run on branch" argument because GitHub looks
      # on that branch for a workflow.yml file, and we'd have to cherry-pick
      # this file into those branches.
      release_branch:

    As always, in FastAPI you can combine `def` and `async def` as needed.

    If you need a refresher about when to use which, check out the section _"In a hurry?"_ in the docs about [`async` and `await`](../async.md#in-a-hurry){.internal-link target=_blank}.

9. This *path operation function* is not returning dataclasses (although it could), but a list of dictionaries with internal data.

**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? { #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 { #oauth2 }