* 데이터 변환
* 데이터 검증
* 자동 문서화

## 특별한 타입과 검증

`str`, `int`, `float` 등과 같은 단일 타입과는 별개로, `str`을 상속하는 더 복잡한 단일 타입을 사용할 수 있습니다.

모든 옵션을 보려면, <a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">Pydantic's exotic types</a> 문서를 확인하세요. 다음 장에서 몇가지 예제를 볼 수 있습니다.

예를 들어 `Image` 모델 안에 `url` 필드를 `str` 대신 Pydantic의 `HttpUrl`로 선언할 수 있습니다:

   *
   * {@snippet :
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
   *         .collect(toImmutableListMultimap(str -> str.charAt(0), str -> str.substring(1)));
   *
   * // is equivalent to
   *
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     new ImmutableListMultimap.Builder<Character, String>()

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: bool = None


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


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


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

        circuitBreaker.call(() -> "success");

        SimpleCircuitBreaker.Statistics stats = circuitBreaker.getStatistics();
        String str = stats.toString();

        assertNotNull(str);
        assertTrue(str.contains("test"));
        assertTrue(str.contains("CLOSED"));
        assertTrue(str.contains("100.00%"));
    }

    @Test
    @DisplayName("Test mixed success and failure pattern")

	fmt.Printf("%s\n", bytes.ToTitle([]byte("брат")))
	// Output:
	// LOUD NOISES
	// БРАТ
}

func ExampleToTitleSpecial() {
	str := []byte("ahoj vývojári golang")
	totitle := bytes.ToTitleSpecial(unicode.AzeriCase, str)
	fmt.Println("Original : " + string(str))
	fmt.Println("ToTitle : " + string(totitle))
	// Output:
	// Original : ahoj vývojári golang
	// ToTitle : AHOJ VÝVOJÁRİ GOLANG
}

        byte[] buf = new byte[12];
        buf[0] = 0x00;
        buf[1] = 0x02; // count = 512 in little-endian
        resp.readParameterWordsWireFormat(buf, 0);
        String str = resp.toString();
        assertTrue(str.contains("count=512"), "toString should include numeric count");
    }

    @Test
    public void testReturnFromReadParameterWordsWireFormatIs8() {
        // ensure the method returns 8 as claimed

В данном примере она преобразует Pydantic модель в `dict`, а `datetime` - в `str`.

Результатом её вызова является объект, который может быть закодирован с помощью функции из стандартной библиотеки Python – <a href="https://docs.python.org/3/library/json.html#json.dumps" class="external-link" target="_blank">`json.dumps()`</a>.

   *
   * {@snippet :
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
   *         .collect(toImmutableListMultimap(str -> str.charAt(0), str -> str.substring(1)));
   *
   * // is equivalent to
   *
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     new ImmutableListMultimap.Builder<Character, String>()

            }
            System.arraycopy(Strings.getUNIBytes(str), 0, dst, dstIndex, str.length() * 2);
            dstIndex += str.length() * 2;
            dst[dstIndex] = (byte) '\0';
            dstIndex++;
            dst[dstIndex++] = (byte) '\0';
        } else {
            final byte[] b = Strings.getOEMBytes(str, this.getConfig());
            System.arraycopy(b, 0, dst, dstIndex, b.length);

        return groupId + ":" + artifactId + ":" + version;
    }

    private static void notBlank(String str, String message) {
        final int strLen = str != null ? str.length() : 0;
        if (strLen > 0) {
            for (int i = 0; i < strLen; i++) {
                if (!Character.isWhitespace(str.charAt(i))) {
                    return;
                }
            }
        }