b[i] = charset[randSrc.Intn(len(charset))]
	}
	return string(b)
}

func genSampleCSVData(count int) []byte {
	buf := &bytes.Buffer{}
	csvWriter := csv.NewWriter(buf)
	csvWriter.Write([]string{"id", "name", "age", "city"})

	for i := range count {
		csvWriter.Write([]string{
			strconv.Itoa(i),
			newRandString(10),
			newRandString(5),
			newRandString(10),
		})
	}

	csvWriter.Flush()
	return buf.Bytes()

Оскільки редактор знає типи змінних, ви не тільки отримаєте автозаповнення, ви також отримаєте перевірку помилок:

<img src="/img/python-types/image04.png">

Тепер ви знаєте, щоб виправити це, вам потрібно перетворити `age` у строку з допомогою `str(age)`:

{* ../../docs_src/python_types/tutorial004.py hl[2] *}


## Оголошення типів

Щойно ви побачили основне місце для оголошення анотацій типу. Як параметри функції.

下面是一个已经有类型提示的函数：

{* ../../docs_src/python_types/tutorial003.py hl[1] *}


因为编辑器已经知道了这些变量的类型，所以不仅能对代码进行补全，还能检查其中的错误：

<img src="https://fastapi.tiangolo.com/img/python-types/image04.png">

现在你知道了必须先修复这个问题，通过 `str(age)` 把 `age` 转换成字符串：

{* ../../docs_src/python_types/tutorial004.py hl[2] *}


## 声明类型

你刚刚看到的就是声明类型提示的主要场景。用于函数的参数。

这也是你将在 **FastAPI** 中使用它们的主要场景。

### 简单类型

In the interest of fostering an open and welcoming environment, we as
contributors and maintainers pledge to make participation in our project and our
community a harassment-free experience for everyone, regardless of age, body
size, disability, ethnicity, gender identity and expression, level of
experience, nationality, personal appearance, race, religion, or sexual identity
and orientation.

## Our Standards

        assertTrue(entry.hasChanges());
        assertTrue(entry.getChildren().isEmpty());
    }

    @Test
    public void testExpiration() {
        // Set a very short max age
        entry.setMaxAge(100); // 100ms

        assertFalse(entry.isExpired());
        assertFalse(entry.needsRefresh());

        // Wait for expiration
        try {
            Thread.sleep(150);

     */
    public int getKeyVersion(String sessionId) {
        return keyVersions.getOrDefault(sessionId, 0);
    }

    /**
     * Get key age in milliseconds
     *
     * @param sessionId the session ID
     * @return age in milliseconds, or -1 if unknown
     */
    public long getKeyAge(String sessionId) {
        Long creationTime = keyCreationTimes.get(sessionId);

{* ../../docs_src/python_types/tutorial003.py hl[1] *}


편집기가 변수의 타입을 알고 있기 때문에, 자동완성 뿐 아니라 에러도 확인할 수 있습니다:

<img src="/img/python-types/image04.png">

이제 고쳐야하는 걸 알기 때문에, `age`를 `str(age)`과 같이 문자열로 바꾸게 됩니다:

{* ../../docs_src/python_types/tutorial004.py hl[2] *}


## 타입 선언

방금 함수의 매개변수로써 타입 힌트를 선언하는 주요 장소를 보았습니다.

이 위치는 여러분이 **FastAPI**와 함께 이를 사용하는 주요 장소입니다.

// row. They have an output for each input row.
//
// Some types of a queries are not valid. For example, an aggregation
// function combined with a row function is meaningless ("AVG(s.Age) +
// s.Salary"). Analysis determines if such a scenario exists so an
// error can be returned.

var (
	// Fatal error for query processing.
	errNestedAggregation      = errors.New("Cannot nest aggregations")

Because the editor knows the types of the variables, you don't only get completion, you also get error checks:

<img src="/img/python-types/image04.png">

Now you know that you have to fix it, convert `age` to a string with `str(age)`:

{* ../../docs_src/python_types/tutorial004_py39.py hl[2] *}

## Declaring types { #declaring-types }

You just saw the main place to declare type hints. As function parameters.

<img src="/img/python-types/image04.png">

Agora você sabe que precisa corrigí-lo, converta `age` em uma string com `str(age)`:

{* ../../docs_src/python_types/tutorial004_py39.py hl[2] *}

## Declarando Tipos { #declaring-types }

Você acabou de ver o local principal para declarar type hints. Como parâmetros de função.