The query parameter `q` is of type `str | None`, that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

Having `str | None` will allow your editor to give you better support and detect errors.

///

//// tab | Python 3.10+

```Python
q: str | None = None
```

////

//// tab | Python 3.8+

```Python
q: Union[str, None] = None
```

////

Тепер ми загорнемо її у `Annotated`, і отримаємо:

//// tab | Python 3.10+

```Python
q: Annotated[str | None] = None
```

////

//// tab | Python 3.8+

```Python
q: Annotated[Union[str, None]] = None
```

////

El parámetro de query `q` es del tipo `Union[str, None]` (o `str | None` en Python 3.10), lo que significa que es de tipo `str` pero también podría ser `None`, y de hecho, el valor por defecto es `None`, así que FastAPI sabrá que no es requerido.

/// note | Nota

FastAPI sabrá que el valor de `q` no es requerido por el valor por defecto `= None`.

➡️ ✊ 👉 🈸 🖼:

{* ../../docs_src/query_params_str_validations/tutorial001.py hl[9] *}

🔢 🔢 `q` 🆎 `Union[str, None]` (⚖️ `str | None` 🐍 3️⃣.1️⃣0️⃣), 👈 ⛓ 👈 ⚫️ 🆎 `str` ✋️ 💪 `None`, & 👐, 🔢 💲 `None`, FastAPI 🔜 💭 ⚫️ 🚫 ✔.

/// note

FastAPI 🔜 💭 👈 💲 `q` 🚫 ✔ ↩️ 🔢 💲 `= None`.

 `Union` `Union[str, None]` 🔜 ✔ 👆 👨‍🎨 🤝 👆 👍 🐕‍🦺 & 🔍 ❌.

///

## 🌖 🔬

//// tab | Python 3.10+

```Python
q: str | None = None
```

////

//// tab | Python 3.8+

```Python
q: Union[str, None] = None
```

////

Вот что мы получим, если обернём это в `Annotated`:

//// tab | Python 3.10+

```Python
q: Annotated[str | None] = None
```

////

//// tab | Python 3.8+

```Python
q: Annotated[Union[str, None]] = None
```

////

Der Query-Parameter `q` hat den Typ `Union[str, None]` (oder `str | None` in Python 3.10), was bedeutet, er ist entweder ein `str` oder `None`. Der Defaultwert ist `None`, also weiß FastAPI, der Parameter ist nicht erforderlich.

/// note | Hinweis

FastAPI weiß nur dank des definierten Defaultwertes `=None`, dass der Wert von `q` nicht erforderlich ist

      }
      String str = builder.toString();
      HashCode hashUtf8 = murmur3_32().hashBytes(str.getBytes(UTF_8));
      assertEquals(hashUtf8, murmur3_32().newHasher().putBytes(str.getBytes(UTF_8)).hash());
      assertEquals(hashUtf8, murmur3_32().hashString(str, UTF_8));
      assertEquals(hashUtf8, murmur3_32().newHasher().putString(str, UTF_8).hash());

     * @param locale the locale
     * @return the converted {@link Date}
     */
    @SuppressWarnings("unchecked")
    protected static Date toDate(final String str, final Locale locale) {
        for (final DateFormat format : iterable(new DateFormatIterator(locale), new PlainDateFormatIterator(str, locale))) {
            if (format == null) {
                continue;
            }

     *
     * @param str the string to encode
     * @param encoding the character encoding to use
     * @return encoded byte array, or empty array if str is null
     */
    public static byte[] getBytes(final String str, final Charset encoding) {
        if (str == null) {
            return new byte[0];
        }
        return str.getBytes(encoding);
    }

    /**

     */
    public Tokenizer(final String str, final byte[] ctype) {
        assertArgumentNotNull("str", str);
        assertArgumentNotEmpty("ctype", ctype);

        this.str = str;
        this.ctype = ctype;
    }

    /**
     * Sets up the character type array.
     *
     * @param ctype2
     *            The array of character types to set up.
     */