```

### Declare a `list` with a type parameter

To declare types that have type parameters (internal types), like `list`, `dict`, `tuple`:

* If you are in a Python version lower than 3.9, import their equivalent version from the `typing` module
* Pass the internal type(s) as "type parameters" using square brackets: `[` and `]`

In Python 3.9 it would be:

```Python
my_list: list[str]
```

    assert response.status_code == 422
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "greater_than",
                    "loc": ["body", "item", "price"],
                    "msg": "Input should be greater than 0",
                    "input": -3.0,
                    "ctx": {"gt": 0.0},
                }
            ]
        }
    ) | IsDict(

    assert response.status_code == 422
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "greater_than",
                    "loc": ["body", "item", "price"],
                    "msg": "Input should be greater than 0",
                    "input": -3.0,
                    "ctx": {"gt": 0.0},
                }
            ]
        }
    ) | IsDict(

使用 `Query` 和 `Path`（以及你将在后面看到的其他类）可以声明字符串约束，但也可以声明数值约束。

像下面这样，添加 `ge=1` 后，`item_id` 将必须是一个大于（`g`reater than）或等于（`e`qual）`1` 的整数。

```Python hl_lines="8"
{!../../../docs_src/path_params_numeric_validations/tutorial004.py!}
```

## 数值校验：大于和小于等于

同样的规则适用于：

* `gt`：大于（`g`reater `t`han）
* `le`：小于等于（`l`ess than or `e`qual）

```Python hl_lines="9"
{!../../../docs_src/path_params_numeric_validations/tutorial005.py!}

And then they can try again knowing that it's probably something more similar to `stanleyjobsox` than to `johndoe`.

#### A "professional" attack

    ```

## Number validations: floats, greater than and less than

Number validations also work for `float` values.

Here's where it becomes important to be able to declare <abbr title="greater than"><code>gt</code></abbr> and not just <abbr title="greater than or equal"><code>ge</code></abbr>. As with it you can require, for example, that a value must be greater than `0`, even if it is less than `1`.

    assert response.status_code == 422
    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "greater_than",
                    "loc": ["body", "item", "price"],
                    "msg": "Input should be greater than 0",
                    "input": -3.0,
                    "ctx": {"gt": 0.0},
                }
            ]
        }
    ) | IsDict(

    assert response.json() == IsDict(
        {
            "detail": [
                {
                    "type": "greater_than",
                    "loc": ["body", 0, "age"],
                    "msg": "Input should be greater than 0",
                    "input": -1.0,
                    "ctx": {"gt": 0},
                }
            ]
        }
    ) | IsDict(

また、数値のバリデーションを宣言することもできます:

* `gt`: より大きい（`g`reater `t`han）
* `ge`: 以上（`g`reater than or `e`qual）
* `lt`: より小さい（`l`ess `t`han）
* `le`: 以下（`l`ess than or `e`qual）

!!! info "情報"
    `Query`、`Path`などは後に共通の`Param`クラスのサブクラスを見ることになります。（使う必要はありません）

    そして、それらすべては、これまで見てきた追加のバリデーションとメタデータと同じパラメータを共有しています。

!!! note "技術詳細"

You send it a token and it returns an authenticated user.

This provider might be charging you per request, and calling it might take some extra time than if you had a fixed mock user for tests.

You probably want to test the external provider once, but not necessarily call it for every test that runs.