# `UploadFile` class

You can define *path operation function* parameters to be of the type `UploadFile` to receive files from the request.

You can import it directly from `fastapi`:

```python
from fastapi import UploadFile
```

::: fastapi.UploadFile
    options:
        members:
            - file
            - filename
            - size
            - headers
            - content_type
            - read

## Technical Details { #technical-details }

The class `BackgroundTasks` comes directly from [`starlette.background`](https://www.starlette.dev/background/).

It is imported/included directly into FastAPI so that you can import it from `fastapi` and avoid accidentally importing the alternative `BackgroundTask` (without the `s` at the end) from `starlette.background`.

/**
 * A generic JUnit test which tests {@code add(int, Object)} operations on a list. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

/**
 * A generic JUnit test which tests {@code remove} operations on a map. Can't be invoked directly;
 * please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author George van den Driessche
 * @author Chris Povirk
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

 *
 * @author Ben Yu
 */
@NullUnmarked
public class AbstractPackageSanityTestsTest extends TestCase {
  /*
   * This is a public type so that the Android test runner can create an instance directly as it
   * insists upon doing. It then runs the test, which behaves exactly like this package's existing
   * PackageSanityTests. (The test would run on the JVM, too, if not for the suppression below, and

/**
 * A generic JUnit test which tests {@code clear()} operations on a map. Can't be invoked directly;
 * please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author George van den Driessche
 * @author Chris Povirk
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@code add(Object)} operations on a list. Can't be invoked
 * directly; please see {@link com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

**FastAPI** 将使用这个*临时*响应来提取头部（也包括 cookies 和状态码），并将它们放入包含你返回的值的最终响应中，该响应由任何 `response_model` 过滤。

你也可以在依赖项中声明 `Response` 参数，并在其中设置头部（和 cookies）。

## 直接返回 `Response` { #return-a-response-directly }

你也可以在直接返回 `Response` 时添加头部。

按照[直接返回响应](response-directly.md)中所述创建响应，并将头部作为附加参数传递：

{* ../../docs_src/response_headers/tutorial001_py310.py hl[10:12] *}

/// note | 技术细节

import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@link Map#computeIfPresent}. Can't be invoked directly; please
 * see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

 * method) of a map. Can't be invoked directly; please see {@link
 * com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Chris Povirk
 * @author Kevin Bourrillion
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")