`dict`を宣言するためには、カンマ区切りで2つの型パラメータを渡します。

最初の型パラメータは`dict`のキーです。

２番目の型パラメータは`dict`の値です。

```Python hl_lines="1 4"
{!../../docs_src/python_types/tutorial008.py!}
```

つまり:

* 変数`prices`は`dict`であり:
    * この`dict`のキーは`str`型です。（つまり、各項目の名前）
    * この`dict`の値は`float`型です。（つまり、各項目の価格）

#### `Optional`

また、`Optional`を使用して、変数が`str`のような型を持つことを宣言することもできますが、それは「オプション」であり、`None`にすることもできます。

func (e SlowDown) Error() string {
	return "Please reduce your request rate"
}

// RQErrType reason for read quorum error.
type RQErrType int

const (
	// RQInsufficientOnlineDrives - not enough online drives.
	RQInsufficientOnlineDrives RQErrType = 1 << iota
	// RQInconsistentMeta - inconsistent metadata.
	RQInconsistentMeta
)

func (t RQErrType) String() string {
	switch t {
	case RQInsufficientOnlineDrives:

   * the full, recursive stack trace of {@code throwable}. Note that you probably should not be
   * parsing the resulting string; if you need programmatic access to the stack frames, you can call
   * {@link Throwable#getStackTrace()}.
   */
  @GwtIncompatible // java.io.PrintWriter, java.io.StringWriter
  public static String getStackTraceAsString(Throwable throwable) {

  /*
   * The basic strategy is to subdivide the table among Segments, each of which itself is a
   * concurrently readable hash table. The map supports non-blocking reads and concurrent writes
   * across different segments.
   *
   * If a maximum size is specified, a best-effort bounding is performed per segment, using a
   * page-replacement algorithm to determine which entries to evict when the capacity has been

							<c:if test="${eoled}">
								<li class="nav-item" data-toggle="tooltip" data-placement="left" title="<la:message key="labels.eol_error" />">
									<a class="nav-link active" href="${eolLink}" target="_olh"><em class="fas fa-times-circle text-danger"></a>
								</li>
							</c:if>
							<c:if test="${developmentMode}">
								<li class="nav-item" data-toggle="tooltip" data-placement="left"

_cgo_export.c and *.cgo2.c, into a dynamic executable and then lets
cgo examine the executable. Cgo records the list of shared library
references and resolved names and writes them into a new file
_cgo_import.go, which looks like:

	//go:cgo_dynamic_linker "/lib64/ld-linux-x86-64.so.2"
	//go:cgo_import_dynamic puts puts#GLIBC_2.2.5 "libc.so.6"

     }
    ```

    You may also skip the retry when you’ve hit an application-defined attempt limit:

    ```kotlin
    if (response.responseCount >= 3) {
      return null // If we've failed 3 times, give up.
    }
    ```

    This above code relies on this `responseCount` extension val:

    ```kotlin
    val Response.responseCount: Int

```

////

//// tab | Python 3.8+

```Python hl_lines="1  4"
{!> ../../docs_src/python_types/tutorial008.py!}
```

////

Isso significa que:

* A variável `prices` é um dict`:
    * As chaves deste `dict` são do tipo `str` (digamos, o nome de cada item).
    * Os valores deste `dict` são do tipo `float` (digamos, o preço de cada item).

#### Union

	}
	if p.errorCount > 0 {
		return nil, false
	}
	p.patch()
	return p.firstProg, true
}

// ParseSymABIs parses p's assembly code to find text symbol
// definitions and references and writes a symabis file to w.
func (p *Parser) ParseSymABIs(w io.Writer) bool {
	operands := make([][]lex.Token, 0, 3)
	for {
		word, _, operands1, ok := p.line(operands)
		if !ok {
			break
		}

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