## Code to get the `username` and `password`

Now let's use the utilities provided by **FastAPI** to handle this.

### `OAuth2PasswordRequestForm`

First, import `OAuth2PasswordRequestForm`, and use it as a dependency with `Depends` in the *path operation* for `/token`:

//// tab | Python 3.10+

```Python hl_lines="4  78"
{!> ../../docs_src/security/tutorial003_an_py310.py!}
```

////

//// tab | Python 3.9+

Lassen Sie uns nun die von **FastAPI** bereitgestellten Werkzeuge verwenden, um das zu erledigen.

### `OAuth2PasswordRequestForm`

Importieren Sie zunächst `OAuth2PasswordRequestForm` und verwenden Sie es als Abhängigkeit mit `Depends` in der *Pfadoperation* für `/token`:

//// tab | Python 3.10+

```Python hl_lines="4  78"
{!> ../../docs_src/security/tutorial003_an_py310.py!}
```

////

//// tab | Python 3.9+

 * remove) are supported. Null keys and values are supported.
 *
 * <p>{@code containsKey(k)}, {@code put(k, v)} and {@code remove(k)} are all (expected and
 * amortized) constant time operations. Expected in the hashtable sense (depends on the hash
 * function doing a good job of distributing the elements to the buckets to a distribution not far
 * from uniform), and amortized since some operations can trigger a hash table resize.
 *

You would probably do this just once, the first time, when setting everything up.

/// tip

This Domain Name part is way before HTTPS, but as everything depends on the domain and the IP address, it's worth mentioning it here.

///

### DNS

Now let's focus on all the actual HTTPS parts.

    if (expected != actual) {
      fail("Expected for " + a + " " + op + " " + b + " = " + expected + ", but got " + actual);
    }
  }

  // Depends on the correctness of BigIntegerMath.factorial.
  @GwtIncompatible // TODO
  public void testFactorial() {
    for (int n = 0; n <= 50; n++) {
      BigInteger expectedBig = BigIntegerMath.factorial(n);

            logger.info("");
            infoLine('-');
            String name = event.getProject().getName();
            infoMain("Skipping " + name);
            logger.info("{} was not built because a module it depends on failed to build.", name);

            infoLine('-');
        }
    }

    @Override
    public void projectStarted(ExecutionEvent event) {
        if (logger.isInfoEnabled()) {
            init();

    assertEquals(
        "Unexpected number of public methods in ReentrantReadWriteLock. "
            + "The correctness of CycleDetectingReentrantReadWriteLock depends on "
            + "the fact that the shadowed ReadLock and WriteLock are never used or "
            + "exposed by the superclass implementation. If the implementation has "

    assertEquals(
        "Unexpected number of public methods in ReentrantReadWriteLock. "
            + "The correctness of CycleDetectingReentrantReadWriteLock depends on "
            + "the fact that the shadowed ReadLock and WriteLock are never used or "
            + "exposed by the superclass implementation. If the implementation has "

	return ""
}

// Returns number of errors that occurred the most (incl. nil) and the
// corresponding error value. NB When there is more than one error value that
// occurs maximum number of times, the error value returned depends on how
// golang's map orders keys. This doesn't affect correctness as long as quorum
// value is greater than or equal to simple majority, since none of the equally
// maximal values would occur quorum or more number of times.

这些细节只是特定的实现方式。

对 OAuth2 来说，都只是字符串而已。

///

## 获取 `username` 和 `password` 的代码

接下来，使用 **FastAPI** 工具获取用户名与密码。

### `OAuth2PasswordRequestForm`

首先，导入 `OAuth2PasswordRequestForm`，然后，在 `/token` *路径操作* 中，用 `Depends` 把该类作为依赖项。

```Python hl_lines="4  76"
{!../../docs_src/security/tutorial003.py!}
```

`OAuth2PasswordRequestForm` 是用以下几项内容声明表单请求体的类依赖项：

* `username`
* `password`
* 可选的 `scope` 字段，由多个空格分隔的字符串组成的长字符串