* or resource constraints) accept without blocking. This is always equal to the initial capacity
   * of this queue less the current {@code size} of this queue.
   *
   * <p>Note that you cannot always tell if an attempt to insert an element will succeed by
   * inspecting {@code remainingCapacity} because it may be the case that another thread is about to
   * insert or remove an element.
   */

        "R0.34, R0.28, R0.25, R0.25", // #5
        "U4.25", // #6
        "R0.00, R0.72, R0.66, R0.59, R0.53, R0.47, R0.41", // #7
        "R0.34, R0.28, R0.25, R0.25"); // #7 (cont.), note, this matches #5
  }

  public void testWarmUpAndUpdateWithColdFactor() {
    RateLimiter limiter = RateLimiter.create(5.0, 4000, MILLISECONDS, 10.0, stopwatch);
    for (int i = 0; i < 8; i++) {

      Collector<Range<E>, ?, ImmutableRangeSet<E>> toImmutableRangeSet() {
    return CollectCollectors.toImmutableRangeSet();
  }

  /**
   * Returns an empty immutable range set.
   *
   * <p><b>Performance note:</b> the instance returned is a singleton.
   */
  @SuppressWarnings("unchecked")
  public static <C extends Comparable> ImmutableRangeSet<C> of() {
    return (ImmutableRangeSet<C>) EMPTY;
  }

  /**

 * in a few ways:
 *
 * <ul>
 *   <li>Each task may be associated with a different executor.
 *   <li>Tasks may be of type {@code AsyncCallable}.
 *   <li>Running tasks <i>cannot</i> be interrupted. (Note that {@code newSequentialExecutor} does
 *       not return {@code Future} objects, so it doesn't support interruption directly, either.
 *       However, utilities that <i>use</i> that executor have the ability to interrupt tasks

```

////

🔢 🔢 🔜 🤔 ⏩:

* 🚥 🔢 📣 **➡**, ⚫️ 🔜 ⚙️ ➡ 🔢.
* 🚥 🔢 **⭐ 🆎** (💖 `int`, `float`, `str`, `bool`, ♒️) ⚫️ 🔜 🔬 **🔢** 🔢.
* 🚥 🔢 📣 🆎 **Pydantic 🏷**, ⚫️ 🔜 🔬 📨 **💪**.

/// note

FastAPI 🔜 💭 👈 💲 `q` 🚫 ✔ ↩️ 🔢 💲 `= None`.

 `Union` `Union[str, None]` 🚫 ⚙️ FastAPI, ✋️ 🔜 ✔ 👆 👨‍🎨 🤝 👆 👍 🐕‍🦺 & 🔍 ❌.

///

## 🍵 Pydantic

const aMCR = arm.ALAST + 1

// IsARMMRC reports whether the op (as defined by an arm.A* constant) is
// MRC or MCR.
func IsARMMRC(op obj.As) bool {
	switch op {
	case arm.AMRC, aMCR: // Note: aMCR is defined in this package.
		return true
	}
	return false
}

// IsARMBFX reports whether the op (as defined by an arm.A* constant) is one the

/// tip

Prefer to use the `Annotated` version if possible.

///

```Python hl_lines="8  49  56-57  60-61  70-76"
{!> ../../docs_src/security/tutorial004.py!}
```

////

/// note | "笔记"

查看新的（伪）数据库 `fake_users_db`，就能看到哈希后的密码：`"$2b$12$EixZaYVK1fsbw1ZfbX3OXePaWxn96p36WQoeG6Lruj3vjPGga31lW"`。

///

## 处理 JWT 令牌

导入已安装的模块。

创建用于 JWT 令牌签名的随机密钥。

使用以下命令，生成安全的随机密钥：

{!../../docs_src/app_testing/tutorial001.py!}
```

/// tip

👀 👈 🔬 🔢 😐 `def`, 🚫 `async def`.

 & 🤙 👩‍💻 😐 🤙, 🚫 ⚙️ `await`.

👉 ✔ 👆 ⚙️ `pytest` 🔗 🍵 🤢.

///

/// note | "📡 ℹ"

👆 💪 ⚙️ `from starlette.testclient import TestClient`.

**FastAPI** 🚚 🎏 `starlette.testclient` `fastapi.testclient` 🏪 👆, 👩‍💻. ✋️ ⚫️ 👟 🔗 ⚪️➡️ 💃.

///

/// tip

 * equals}, {@code hashCode} and {@code compareTo} because instances are expected to be mutated, and
 * so are not useful as collection keys.
 *
 * <p>jsr166e note: This class is targeted to be placed in java.util.concurrent.atomic.
 *
 * @since 1.8
 * @author Doug Lea
 */
@ElementTypesAreNonnullByDefault

 * equals}, {@code hashCode} and {@code compareTo} because instances are expected to be mutated, and
 * so are not useful as collection keys.
 *
 * <p>jsr166e note: This class is targeted to be placed in java.util.concurrent.atomic.
 *
 * @since 1.8
 * @author Doug Lea
 */
@ElementTypesAreNonnullByDefault