`@Deprecated` APIs will remain (again, unless they are `@Beta`). We have no
    plans to start removing things again, but officially, we're leaving our
    options open in case of surprises (like, say, a serious security problem).

3.  Guava has one dependency that is needed for linkage at runtime:
    `com.google.guava:failureaccess:1.0.3`. It also has
    [some annotation-only dependencies][guava-deps], which we discuss in more

#### 字典 { #dict }

定义 `dict` 时，需要传入 2 个类型参数，用逗号分隔。

第一个类型参数用于字典的键。

第二个类型参数用于字典的值：

{* ../../docs_src/python_types/tutorial008_py310.py hl[1] *}

这表示：

* 变量 `prices` 是一个 `dict`：
    * 这个 `dict` 的键是 `str` 类型（比如，每个条目的名称）。
    * 这个 `dict` 的值是 `float` 类型（比如，每个条目的价格）。

#### Union { #union }

你可以声明一个变量可以是若干种类型中的任意一种，比如既可以是 `int` 也可以是 `str`。

				// and should never happen - however it has
				// been seen recently due to hardware issues
				// causes Reads() to go slower than Writes().
				//
				// Send such results anyways as this shall
				// expose a problem underneath.
				if totalPut > throughputHighestPut {
					throughputHighestResults = results
					throughputHighestPut = totalPut
					// let the client see lower value as well
					throughputHighestGet = totalGet

        }
        Type[] resolvedBounds = new TypeResolver(forDependants).resolveTypes(bounds);
        /*
         * We'd like to simply create our own TypeVariable with the newly resolved bounds. There's
         * just one problem: We want to interoperate properly with the platform's built-in
         * implementation of TypeVariable, but the behavior of the built-in implementation differs
         * across platforms:
         *

   * for an RPC may wait for a similar call that requests a long timeout, or a call by an
   * unprivileged user may return a resource accessible only to a privileged user making a similar
   * call. To prevent this problem, create a key object that includes all values that affect the
   * result of the query. Or use {@code LoadingCache.get(K)}, which lacks the ability to refer to
   * state other than that in the key.
   *

	// Verify if region is valid.
	sRegion := cred.scope.region
	// Region is set to be empty, we use whatever was sent by the
	// request and proceed further. This is a work-around to address
	// an important problem for ListBuckets() getting signed with
	// different regions.
	if region == "" {
		region = sRegion
	}
	// Should validate region, only if region is set.
	if !isValidRegion(sRegion, region) {

                // Don't want to have two workers pulling from the queue.
                return;
              } else {
                // Increment the run counter to avoid the ABA problem of a submitter marking the
                // thread as QUEUED after it already ran and exhausted the queue before returning
                // from execute().
                workerRunCount++;

`dict`를 정의하려면, 쉼표로 구분된 2개의 타입 매개변수를 전달합니다.

첫 번째 타입 매개변수는 `dict`의 키를 위한 것입니다.

두 번째 타입 매개변수는 `dict`의 값을 위한 것입니다:

{* ../../docs_src/python_types/tutorial008_py310.py hl[1] *}

이는 다음을 의미합니다:

* 변수 `prices`는 `dict`입니다:
    * 이 `dict`의 키는 `str` 타입입니다(예: 각 아이템의 이름).
    * 이 `dict`의 값은 `float` 타입입니다(예: 각 아이템의 가격).

#### Union { #union }

변수가 **여러 타입 중 어떤 것이든** 될 수 있다고 선언할 수 있습니다. 예를 들어 `int` 또는 `str`입니다.

 * {@code .compare(a.foo, b.foo)} but you actually wrote {@code .compare(a.foo, a.foo)} or {@code
 * .compare(a.foo, b.bar)}. {@code ComparisonChain} also has a potential performance problem that
 * {@code Comparator} doesn't: it evaluates all the parameters of all the {@code .compare} calls,
 * even when the result of the comparison is already known from previous {@code .compare} calls.
 * That can be expensive.
 *

last the Dodo said, `EVERYBODY has won, and all must have
prizes.'

  `But who is to give the prizes?' quite a chorus of voices
asked.

  `Why, SHE, of course,' said the Dodo, pointing to Alice with
one finger; and the whole party at once crowded round her,
calling out in a confused way, `Prizes! Prizes!'

  Alice had no idea what to do, and in despair she put her hand