{* ../../docs_src/security/tutorial001_an_py39.py hl[12] *}

This dependency will provide a `str` that is assigned to the parameter `token` of the *path operation function*.

**FastAPI** will know that it can use this dependency to define a "security scheme" in the OpenAPI schema (and the automatic API docs).

/// info | Technical Details

  <!-- localRepository
   | The path to the local repository maven will use to store artifacts.
   |
   | Default: ${user.home}/.m2/repository
  <localRepository>/path/to/local/repo</localRepository>
  -->

  <!-- interactiveMode
   | This will determine whether maven prompts you when it needs input. If set to false,
   | maven will use a sensible default value, perhaps based on some other setting, for

                            * `security_scopes.scopes` will contain `["me", "items"]` for the *path operation* `read_own_items`.
                            * `security_scopes.scopes` will contain `["me"]` for the *path operation* `read_users_me`, because it is declared in the dependency `get_current_active_user`.

   *
   * <p>Exceptions thrown by a listener will be propagated up to the executor. Any exception thrown
   * during {@code Executor.execute} (e.g., a {@code RejectedExecutionException} or an exception
   * thrown by {@linkplain MoreExecutors#directExecutor direct execution}) will be caught and
   * logged.
   *
   * <p>Note: If your listener is lightweight -- and will not cause stack overflow by completing

     * specified by the <code>UniAddress</code> parameter. If the credentials are
     * not accepted, an <code>SmbAuthException</code> will be thrown. If an error
     * occurs an <code>SmbException</code> will be thrown. If the credentials are
     * valid, the method will return without throwing an exception. See the
     * last <a href="../../../faq.html">FAQ</a> question.
     * <p>

     * The error's stacktrace will be output when this error level is enabled.
     *
     * @param content the message to log
     * @param error the error that caused this log
     */
    void debug(CharSequence content, Throwable error);

    /**
     * Sends an exception to the user in the <b>debug</b> error level.
     * The stack trace for this exception will be output when this error level is enabled.
     *

/// tip

All this might not seem as useful with these simple examples.

But you will see how useful it is in the chapters about **security**.

And you will also see the amounts of code it will save you.

You can write <a href="https://en.wikipedia.org/wiki/Markdown" class="external-link" target="_blank">Markdown</a> in the docstring, it will be interpreted and displayed correctly (taking into account docstring indentation).

{* ../../docs_src/path_operation_configuration/tutorial004_py310.py hl[17:25] *}

It will be used in the interactive docs:

///

The dependencies will keep working as expected, and the **best part** is that the **type information will be preserved**, which means that your editor will be able to keep providing you with **autocompletion**, **inline errors**, etc. The same for other tools like `mypy`.

     *
     * @param dataset the dataset to do the calculation on, which must be non-empty, which will be
     *     cast to doubles (with any associated lost of precision), and which will not be mutated by
     *     this call (it is copied instead)
     * @return an unmodifiable, ordered map of results: the keys will be the specified quantile