* Converts the specified {@code String str} from this format to the specified {@code format}. A
   * "best effort" approach is taken; if {@code str} does not conform to the assumed format, then
   * the behavior of this method is undefined but we make a reasonable effort at converting anyway.
   */
  public final String to(CaseFormat format, String str) {
    checkNotNull(format);
    checkNotNull(str);

#### `Optional`

`str`과 같이 타입을 선언할 때 `Optional`을 쓸 수도 있는데, "선택적(Optional)"이기때문에 `None`도 될 수 있습니다:

```Python hl_lines="1  4"
{!../../docs_src/python_types/tutorial009.py!}
```

`Optional[str]`을 `str` 대신 쓰게 되면, 특정 값이 실제로는 `None`이 될 수도 있는데 항상 `str`이라고 가정하는 상황에서 에디터가 에러를 찾게 도와줄 수 있습니다.

#### Generic(제네릭) 타입

이 타입은 대괄호 안에 매개변수를 가지며, 종류는:

* `List`
* `Tuple`
* `Set`
* `Dict`

     * Encodes a wide string pointer in NDR format.
     *
     * @param buf the NDR buffer
     * @param str the string to encode (can be null)
     * @throws NdrException if encoding fails
     */
    private void encodeWideStringPointer(NdrBuffer buf, String str) throws NdrException {
        if (str == null || str.isEmpty()) {
            buf.enc_ndr_long(0); // NULL pointer
        } else {

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


@app.put("/items/{item_id}")

In diesem Beispiel wird das Pydantic-Modell in ein `dict`, und das `datetime`-Objekt in ein `str` konvertiert.

Das Resultat dieses Aufrufs ist etwas, das mit Pythons Standard-<a href="https://docs.python.org/3/library/json.html#json.dumps" class="external-link" target="_blank">`json.dumps()`</a> kodiert werden kann.

        assertEquals(FileInformation.FILE_ENDOFFILE_INFO, fileInfoWithEof.getFileInformationLevel());

        // Test toString
        String str = fileInfoWithEof.toString();
        assertNotNull(str);
        assertTrue(str.contains("EndOfFileInformation"));
        assertTrue(str.contains("1024"));
    }

    /**
     * Test FileEndOfFileInformation encode/decode round trip
     */
    @Test

///

## ⚫️❔ ⚫️ 🔨

⚫️ 🔜 🚶 & 👀 📨 👈 `Authorization` 🎚, ✅ 🚥 💲 `Bearer ` ➕ 🤝, & 🔜 📨 🤝 `str`.

🚥 ⚫️ 🚫 👀 `Authorization` 🎚, ⚖️ 💲 🚫 ✔️ `Bearer ` 🤝, ⚫️ 🔜 📨 ⏮️ 4️⃣0️⃣1️⃣ 👔 📟 ❌ (`UNAUTHORIZED`) 🔗.

👆 🚫 ✔️ ✅ 🚥 🤝 🔀 📨 ❌. 👆 💪 💭 👈 🚥 👆 🔢 🛠️, ⚫️ 🔜 ✔️ `str` 👈 🤝.

👆 💪 🔄 ⚫️ ⏪ 🎓 🩺:

<img src="/img/tutorial/security/image03.png">

👥 🚫 ✔ 🔬 🤝, ✋️ 👈 ▶️ ⏪.

En este ejemplo, convertiría el modelo de Pydantic a un `dict`, y el `datetime` a un `str`.

El resultado de llamarlo es algo que puede ser codificado con la función estándar de Python <a href="https://docs.python.org/3/library/json.html#json.dumps" class="external-link" target="_blank">`json.dumps()`</a>.

        }
        write(b, 0, blen);
    }

    @Override
    public final void writeUTF(final String str) throws SmbException {
        final int len = str.length();
        int ch, size = 0;
        byte[] dst;

        for (int i = 0; i < len; i++) {
            ch = str.charAt(i);
            size += ch > 0x07F ? ch > 0x7FF ? 3 : 2 : 1;
        }
        dst = new byte[size];

```Python
from datetime import date

from pydantic import BaseModel

# Déclare une variable comme étant une str
# et profitez de l'aide de votre IDE dans cette fonction
def main(user_id: str):
    return user_id


# Un modèle Pydantic
class User(BaseModel):
    id: int
    name: str
    joined: date
```
Qui peuvent ensuite être utilisés comme cela:

```Python