///

/// note | "笔记"

因为默认值为 `= None`，FastAPI 把 `q` 识别为可选参数。

FastAPI 不使用 `Optional[str]` 中的 `Optional`（只使用 `str`），但 `Optional[str]` 可以帮助编辑器发现代码中的错误。

///

## 查询参数类型转换

参数还可以声明为 `bool` 类型，FastAPI 会自动转换参数类型：


//// tab | Python 3.10+

```Python hl_lines="7"
{!> ../../docs_src/query_params/tutorial003_py310.py!}
```

////

//// tab | Python 3.8+

		sps := SerializerPostgresStruct(*s)
		return &sps
	}
	return s
}

type Roles []string

type Job struct {
	Title    string
	Number   int
	Location string
	IsIntern bool
}

type EncryptedString string

func (es *EncryptedString) Scan(ctx context.Context, field *schema.Field, dst reflect.Value, dbValue interface{}) (err error) {
	switch value := dbValue.(type) {
	case []byte:

	ReqParams    map[string]string
	RespElements map[string]string
	Host         string
	UserAgent    string
}

// ToEvent - converts to notification event.
func (args eventArgs) ToEvent(escape bool) event.Event {
	eventTime := UTCNow()
	uniqueID := fmt.Sprintf("%X", eventTime.UnixNano())
	if !args.Object.ModTime.IsZero() {
		uniqueID = fmt.Sprintf("%X", args.Object.ModTime.UnixNano())
	}

		webhooksBefore   admitv1.MutatingWebhookConfigurationList
		webhooksAfter    admitv1.MutatingWebhookConfigurationList
		namespaces       corev1.NamespaceList
		outputMatches    []string
		skipConfirmation bool
		error            string
	}{
		{
			name: "TestSimpleRemove",
			tag:  "sample",
			webhooksBefore: admitv1.MutatingWebhookConfigurationList{
				Items: []admitv1.MutatingWebhookConfiguration{
					{

Python hat Unterstützung für optionale „Typhinweise“ (Englisch: „Type Hints“). Auch „Typ Annotationen“ genannt.

Diese **„Typhinweise“** oder -Annotationen sind eine spezielle Syntax, die es erlaubt, den <abbr title="Zum Beispiel: str, int, float, bool">Typ</abbr> einer Variablen zu deklarieren.

Durch das Deklarieren von Typen für Ihre Variablen können Editoren und Tools bessere Unterstützung bieten.

// deadlocks.
class DeviceThread {
 public:
  // Starts a background thread waiting for `StartExecute`.
  explicit DeviceThread(const std::string& device, const bool is_async,
                        const int in_flight_nodes_limit)
      : status_(TF_NewStatus()),
        // If the context's default exector is set to async, re-using that in

	}
	if testOut != nil {
		fmt.Fprintln(testOut, prog)
	}
}

// validSymbol checks that addr represents a valid name for a pseudo-op.
func (p *Parser) validSymbol(pseudo string, addr *obj.Addr, offsetOk bool) bool {
	if addr.Sym == nil || addr.Name != obj.NAME_EXTERN && addr.Name != obj.NAME_STATIC || addr.Scale != 0 || addr.Reg != 0 {
		p.errorf("%s symbol %q must be a symbol(SB)", pseudo, symbolName(addr))
		return false
	}

	fmt.Println(bytes.ContainsRune([]byte(""), '@'))
	// Output:
	// true
	// false
	// true
	// true
	// false
}

func ExampleContainsFunc() {
	f := func(r rune) bool {
		return r >= 'a' && r <= 'z'
	}
	fmt.Println(bytes.ContainsFunc([]byte("HELLO"), f))
	fmt.Println(bytes.ContainsFunc([]byte("World"), f))
	// Output:
	// false
	// true
}

func ExampleCount() {

// domain is "SSE-KMS".
func (ssekms) String() string { return "SSE-KMS" }

// IsRequested returns true if the HTTP headers contains
// at least one SSE-KMS header.
func (ssekms) IsRequested(h http.Header) bool {
	if _, ok := h[xhttp.AmzServerSideEncryptionKmsID]; ok {
		return true
	}
	if _, ok := h[xhttp.AmzServerSideEncryptionKmsContext]; ok {
		return true
	}
	if _, ok := h[xhttp.AmzServerSideEncryption]; ok {

  if not parsed_args.print and not parsed_args.xml_out_path:
    raise TypeError('`--print` or `--xml-out-path` must be specified')

  return parsed_args


def parse_log(file_path: str,
              verbose: bool = False) -> ResultDictType:
  """Finds ResultStore links, and tries to determine their status."""
  with open(file_path, 'r', encoding='utf-8', errors='ignore') as f:
    log_lines = f.read().splitlines()