So:

```Python
q: Union[str, None] = Query(default=None)
```

...makes the parameter optional, with a default value of `None`, the same as:

```Python

  /**
   * Stores a collection of values with the same key, replacing any existing values for that key.
   *
   * <p>Because a {@code SortedSetMultimap} has unique sorted values for a given key, this method
   * returns a {@link SortedSet}, instead of the {@link java.util.Collection} specified in the
   * {@link Multimap} interface.
   *
   * <p>Any duplicates in {@code values} will be stored in the multimap once.
   */

cert-secret-volume secret: secretName: {{ .Values.tls.certSecret }} items: - key: {{ .Values.tls.publicCrt }} path: public.crt - key: {{ .Values.tls.privateKey }} path: private.key {{- end }} {{- if or .Values.tls.enabled (ne .Values.trustedCertsSecret "") }} {{- $certSecret := eq .Values.trustedCertsSecret "" | ternary .Values.tls.certSecret .Values.trustedCertsSecret }} {{- $publicCrt := eq .Values.trustedCertsSecret "" | ternary .Values.tls.publicCrt "" }} - name: trusted-cert-secret-volume secret: secretName:...

    Set<K> ks = keySet;
    return (ks != null) ? ks : (keySet = new KeySet(this));
  }

  Collection<V> values;

  @Override
  public Collection<V> values() {
    // does not impact recency ordering
    Collection<V> vs = values;
    return (vs != null) ? vs : (values = new Values(this));
  }

  Set<Entry<K, V>> entrySet;

  @Override
  public Set<Entry<K, V>> entrySet() {

/**
 * Implementation of {@link Multimap} using hash tables.
 *
 * <p>The multimap does not store duplicate key-value pairs. Adding a new key-value pair equal to an
 * existing key-value pair has no effect.
 *
 * <p>Keys and values may be null. All optional multimap methods are supported, and all returned
 * views are modifiable.
 *

cert-secret-volume secret: secretName: {{ .Values.tls.certSecret }} items: - key: {{ .Values.tls.publicCrt }} path: public.crt - key: {{ .Values.tls.privateKey }} path: private.key {{- end }} {{- if or .Values.tls.enabled (ne .Values.trustedCertsSecret "") }} {{- $certSecret := eq .Values.trustedCertsSecret "" | ternary .Values.tls.certSecret .Values.trustedCertsSecret }} {{- $publicCrt := eq .Values.trustedCertsSecret "" | ternary .Values.tls.publicCrt "" }} - name: trusted-cert-secret-volume secret: secretName:...

cert-secret-volume secret: secretName: {{ .Values.tls.certSecret }} items: - key: {{ .Values.tls.publicCrt }} path: public.crt - key: {{ .Values.tls.privateKey }} path: private.key {{- end }} {{- if or .Values.tls.enabled (ne .Values.trustedCertsSecret "") }} {{- $certSecret := eq .Values.trustedCertsSecret "" | ternary .Values.tls.certSecret .Values.trustedCertsSecret }} {{- $publicCrt := eq .Values.trustedCertsSecret "" | ternary .Values.tls.publicCrt "" }} - name: trusted-cert-secret-volume secret: secretName:...

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @Override
  V checkValue(V value) {
    return checkNotNull(value);
  }

  /**
   * @serialData the key class, value class, number of entries, first key, first value, second key,
   *     second value, and so on.
   */
  @GwtIncompatible // java.io.ObjectOutputStream
  private void writeObject(ObjectOutputStream stream) throws IOException {

  @Override
  K checkKey(K key) {
    return checkNotNull(key);
  }

  @Override
  V checkValue(V value) {
    return checkNotNull(value);
  }

  /**
   * @serialData the key class, value class, number of entries, first key, first value, second key,
   *     second value, and so on.
   */
  @GwtIncompatible // java.io.ObjectOutputStream
  private void writeObject(ObjectOutputStream stream) throws IOException {

///

```Python hl_lines="8  13"
{!> ../../docs_src/dependencies/tutorial006.py!}
```

////

### 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:

//// tab | Python 3.9+

```Python hl_lines="11  16"