idea was that she had somehow fallen into the sea, `and in that
case I can go back by railway,' she said to herself.  (Alice had
been to the seaside once in her life, and had come to the general
conclusion, that wherever you go to on the English coast you find
a number of bathing machines in the sea, some children digging in
the sand with wooden spades, then a row of lodging houses, and
behind them a railway station.)  However, she soon made out that

Now that we have **multiple models**, we can update the parts of the app that use them.

We receive in the request a `HeroCreate` *data model*, and from it, we create a `Hero` *table model*.

This new *table model* `Hero` will have the fields sent by the client, and will also have an `id` generated by the database.

{* ../../docs_src/header_param_models/tutorial001_an_py310.py hl[9:14,18] *}

**FastAPI** will **extract** the data for **each field** from the **headers** in the request and give you the Pydantic model you defined.

## Check the Docs { #check-the-docs }

You can see the required headers in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/header-param-models/image01.png">
</div>

     * which pages you deem most important for the crawlers.
     *
     * The default priority of a page is 0.5.
     *
     * Please note that the priority you assign to a page is not likely to
     * influence the position of your URLs in a search engine's result pages.
     * Search engines may use this information when selecting between URLs on
     * the same site, so you can use this tag to increase the likelihood that

     * The iteration order is the order in which the sources are declared in the POM file.
     *
     * @param project the project for which to get the source roots
     */
    @Nonnull
    Collection<SourceRoot> getSourceRoots(@Nonnull Project project);

    /**
     * {@return all enabled sources that provide files in the given language for the given scope}.

This is because it is expected that **your users** would define the actual **URL path** where they want to receive the webhook request in some other way (e.g. a web dashboard).

### Check the docs { #check-the-docs }

These dependencies can `raise` exceptions, the same as normal dependencies:

{* ../../docs_src/dependencies/tutorial006_an_py39.py hl[10,15] *}

### Return values { #return-values }

And they can return values or not, the values won't be used.

So, you can reuse a normal dependency (that returns a value) you already use somewhere else, and even though the value won't be used, the dependency will be executed:

* the data from the client to be sent through the network
* the data sent by your program to be received by the client through the network
* the contents of a file in the disk to be read by the system and given to your program
* the contents your program gave to the system to be written to disk
* a remote API operation

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

/**
 * A unit of work that can be executed one or more times.
 *
 * Recurrence
 * ----------
 *
 * Tasks control their recurrence schedule. The [runOnce] function returns -1L to signify that the
 * task should not be executed again. Otherwise it returns a delay until the next execution.

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