Prefiere usar la versión `Annotated` si es posible.

///

```Python
commons: CommonQueryParams ...
```

////

...no tiene ningún significado especial para **FastAPI**. **FastAPI** no lo usará para la conversión de datos, validación, etc. (ya que está usando `Depends(CommonQueryParams)` para eso).

De hecho, podrías escribir simplemente:

//// tab | Python 3.9+

```Python

That means that **any value** read in Python from an environment variable **will be a `str`**, and any conversion to a different type or any validation has to be done in code.

This can be very useful for setting up **resources** that you need to use for the whole app, and that are **shared** among requests, and/or that you need to **clean up** afterwards. For example, a database connection pool, or loading a shared machine learning model.

## Use Case { #use-case }

Let's start with an example **use case** and then see how to solve it with this.

                    cipherSuites(*cipherSuites.toTypedArray())
                  }
                }.build(),
            ),
          )
        }
      }.addNetworkInterceptor {
        val socket = it.connection()!!.socket() as SSLSocket

        handshakeEnabledCipherSuites = socket.enabledCipherSuites.toList()

        it.proceed(it.request())
      }.build()

        <otherArchive>http://maven.notifications.markmail.org/</otherArchive>
      </otherArchives>
    </mailingList>
  </mailingLists>
  <scm>
    <connection>scm:svn:http://svn.apache.org/repos/asf/maven/components/trunk</connection>
    <developerConnection>scm:svn:https://svn.apache.org/repos/asf/maven/components/trunk</developerConnection>
    <url>http://svn.apache.org/viewcvs.cgi/maven/components/trunk</url>

    * <abbr title="en anglais : forms">les formulaires</abbr>.
    * <abbr title="en anglais : files">les fichiers</abbr>.
* <abbr title="aussi connu sous le nom de : serialization, parsing, marshalling">La conversion</abbr> des données de sortie : conversion des données et types Python en données réseau (au format <abbr title="JavaScript Object Notation">JSON</abbr>), permettant de convertir :
    * les types Python (`str`, `int`, `float`, `bool`, `list`, etc).

        <otherArchive>http://maven.notifications.markmail.org/</otherArchive>
      </otherArchives>
    </mailingList>
  </mailingLists>
  <scm>
    <connection>scm:svn:http://svn.apache.org/repos/asf/maven/components/trunk</connection>
    <developerConnection>scm:svn:https://svn.apache.org/repos/asf/maven/components/trunk</developerConnection>
    <url>http://svn.apache.org/viewcvs.cgi/maven/components/trunk</url>

	public fun connectStart (Lokhttp3/Call;Ljava/net/InetSocketAddress;Ljava/net/Proxy;)V
	public fun connectionAcquired (Lokhttp3/Call;Lokhttp3/Connection;)V
	public fun connectionReleased (Lokhttp3/Call;Lokhttp3/Connection;)V
	public fun dispatcherQueueEnd (Lokhttp3/Call;Lokhttp3/Dispatcher;)V
	public fun dispatcherQueueStart (Lokhttp3/Call;Lokhttp3/Dispatcher;)V

Now, the STS certificate-based authentication happens in 4 steps:

- Client sends HTTP `POST` request over a TLS connection hitting the MinIO TLS STS API.
- MinIO verifies that the client certificate is valid.
- MinIO tries to find a policy that matches the `CN` of the client certificate.

Dadurch erhalten Sie Editor-Unterstützung innerhalb Ihrer Funktion, mit Fehlerprüfungen, Codevervollständigung, usw.

///

## Daten-<abbr title="Auch bekannt als: Serialisierung, Parsen, Marshalling">Konversion</abbr> { #data-conversion }

Wenn Sie dieses Beispiel ausführen und Ihren Browser unter <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a> öffnen, sehen Sie als Response:

```JSON