And also that your code will be very compatible with many other Python tools and libraries. 🚀

///

## Type hints in **FastAPI** { #type-hints-in-fastapi }

**FastAPI** takes advantage of these type hints to do several things.

With **FastAPI** you declare parameters with type hints and you get:

* **Editor support**.
* **Type checks**.

...and **FastAPI** uses the same declarations to:

It had automatic data validation, data serialization and OpenAPI schema generation based on the same type hints in several places.

  /**
   * The HTTP <a href="https://wicg.github.io/ua-client-hints/#sec-ch-ua-arch">{@code
   * Sec-CH-UA-Arch}</a> header field name.
   *
   * @since 30.0
   */
  public static final String SEC_CH_UA_ARCH = "Sec-CH-UA-Arch";

  /**
   * The HTTP <a href="https://wicg.github.io/ua-client-hints/#sec-ch-ua-model">{@code
   * Sec-CH-UA-Model}</a> header field name.
   *
   * @since 30.0

Example:

Source (English):

```
## Type hints and annotations { #type-hints-and-annotations }
```

Translate with (German) - notice the hyphen:

```
## Typhinweise und -annotationen { #type-hints-and-annotations }
```

Do NOT translate with (German) - notice the dash:

```
## Typhinweise und –annotationen { #type-hints-and-annotations }
```

      limit = pushedLimit
      constructed = pushedConstructed
      if (name != null) path.removeAt(path.size - 1)
    }
  }

  /**
   * Execute [block] with a new namespace for type hints. Type hints from the enclosing type are no
   * longer usable by the current type's members.
   */
  fun <T> withTypeHint(block: () -> T): T {
    typeHintStack.add(null)
    try {
      return block()
    } finally {

        Map<Object, Object> hints = new HashMap<>();
        String childPath = child.getProperties().getProperty(CHILD_DIRECTORY_PROPERTY, child.getArtifactId());
        hints.put(CHILD_DIRECTORY, childPath);
        hints.put(MavenModelMerger.CHILD_PATH_ADJUSTMENT, getChildPathAdjustment(child, parent, childPath));
        merger.merge(child, parent, false, hints);
    }

    /**

## Headings { #headings }

//// tab | Test

### Develop a webapp - a tutorial { #develop-a-webapp-a-tutorial }

Hello.

### Type hints and -annotations { #type-hints-and-annotations }

Hello again.

### Super- and subclasses { #super-and-subclasses }

Hello again.

////

//// tab | Info

/// info | 信息

想了解更多关于 [Pydantic](https://docs.pydantic.dev/) 的信息，请查看其文档。

///

**FastAPI** 完全建立在 Pydantic 之上。

你会在[教程 - 用户指南](tutorial/index.md)中看到更多的实战示例。

## 带元数据注解的类型提示 { #type-hints-with-metadata-annotations }

Python 还提供了一个特性，可以使用 `Annotated` 在这些类型提示中放入额外的<dfn title="关于数据的数据，此处指关于类型的信息，例如描述。">元数据</dfn>。

你可以从 `typing` 导入 `Annotated`。

/// info | 資訊

想了解更多 [Pydantic，請查看它的文件](https://docs.pydantic.dev/)。

///

**FastAPI** 完全是以 Pydantic 為基礎。

你會在[教學 - 使用者指南](tutorial/index.md)中看到更多實際範例。

## 含中繼資料的型別提示 { #type-hints-with-metadata-annotations }

Python 也有一個功能，允許使用 `Annotated` 在這些型別提示中放入額外的<dfn title="關於資料的資料；在此情境下，是關於型別的資訊，例如描述。">中繼資料</dfn>。

你可以從 `typing` 匯入 `Annotated`。

            assertEquals(0x12345, req.getMinCount(), "minCount should remain original full value");
        }

        @Test
        @DisplayName("Named pipe request uses fixed 1024 hints")
        void namedPipeRequestHints() throws Exception {
            when(mockTree.isSMB2()).thenReturn(false);
            when(mockFile.getType()).thenReturn(SmbConstants.TYPE_NAMED_PIPE);