Nur, dass die `Query`-Versionen den Parameter explizit als Query-Parameter deklarieren.

/// info

Bedenken Sie, dass:

```Python
= None
```

oder:

```Python
= Query(default=None)
```

der wichtigste Teil ist, um einen Parameter optional zu machen, da dieses `None` der Defaultwert ist, und das ist es, was diesen Parameter **nicht erforderlich** macht.

Both of those versions mean the same thing, `q` is a parameter that can be a `str` or `None`, and by default, it is `None`.

Now let's jump to the fun stuff. 🎉

## Add `Query` to `Annotated` in the `q` parameter { #add-query-to-annotated-in-the-q-parameter }

Now that we have this `Annotated` where we can put more information (in this case some additional validation), add `Query` inside of `Annotated`, and set the parameter `max_length` to `50`:

   * the dummy value of a constructor or method parameter is unknown.
   */
  @VisibleForTesting
  static final class ParameterNotInstantiableException extends Exception {
    public ParameterNotInstantiableException(Parameter parameter) {
      super(
          "Cannot determine value for parameter "
              + parameter
              + " of "
              + parameter.getDeclaringInvokable());
    }
  }

///

### Deklarieren Sie einen *Pfad-Parameter*

Dann erstellen Sie einen *Pfad-Parameter*, der als Typ die gerade erstellte Enum-Klasse hat (`ModelName`):

{* ../../docs_src/path_params/tutorial005.py hl[16] *}

### Testen Sie es in der API-Dokumentation

Weil die erlaubten Werte für den *Pfad-Parameter* nun vordefiniert sind, kann die interaktive Dokumentation sie als Auswahl-Drop-Down anzeigen:

 * types, and also for interfaces and public classes that have public parameter-less constructors.
 * When the non-null default value for a particular parameter type cannot be provided by {@code
 * NullPointerTester}, the caller can provide a custom non-null default value for the parameter type
 * via {@link #setDefault}.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 */
@GwtIncompatible

   * the dummy value of a constructor or method parameter is unknown.
   */
  @VisibleForTesting
  static final class ParameterNotInstantiableException extends Exception {
    public ParameterNotInstantiableException(Parameter parameter) {
      super(
          "Cannot determine value for parameter "
              + parameter
              + " of "
              + parameter.getDeclaringInvokable());
    }
  }

     * Set the value of hostname, used in parameter comment. <br>
     * Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.
     * @param hostname The parameter value of hostname. (NotNull)
     */
    public void setHostname(String hostname) {
        registerVariable("hostname", hostname);
    }

    /**
     * Set the value of jobname, used in parameter comment. <br>

        // Verify total parameter count (4 bytes at position 3)
        assertEquals(100, SMBUtil.readInt4(dst, 3));

        // Verify total data count (4 bytes at position 7)
        assertEquals(200, SMBUtil.readInt4(dst, 7));

        // Verify parameter count (4 bytes at position 11)
        assertEquals(30, SMBUtil.readInt4(dst, 11));

        // Verify parameter offset (4 bytes at position 15)

You can use the `response_model` parameter in any of the *path operations*:

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* etc.

{* ../../docs_src/response_model/tutorial001_py310.py hl[17,22,24:27] *}

/// note

    /** Total number of parameter bytes the server is returning */
    protected int totalParameterCount;
    /** Total number of data bytes the server is returning */
    protected int totalDataCount;
    /** Number of parameter bytes in this response */
    protected int parameterCount;
    /** Offset from the start of the SMB header to the parameter bytes */
    protected int parameterOffset;