Sie können auch eine Response deklarieren, die ein beliebiges `dict` zurückgibt, indem Sie nur die Typen der Schlüssel und Werte ohne ein Pydantic-Modell deklarieren.

Dies ist nützlich, wenn Sie die gültigen Feld-/Attributnamen nicht im Voraus kennen (die für ein Pydantic-Modell benötigt werden würden).

In diesem Fall können Sie `typing.Dict` verwenden (oder nur `dict` in Python 3.9 und höher):

			defer wg.Done()
			var buf [1]byte
			r.ReadAt(buf[:], int64(i))
		}(i)
	}
	wg.Wait()
}

func TestEmptyReaderConcurrent(t *testing.T) {
	// Test for the race detector, to verify a Read that doesn't yield any bytes
	// is okay to use from multiple goroutines. This was our historic behavior.
	// See golang.org/issue/7856
	r := NewReader([]byte{})
	var wg sync.WaitGroup
	for i := 0; i < 5; i++ {
		wg.Add(2)

	DeadlineMS uint32    // If non-zero, milliseconds until deadline (max 1193h2m47.295s, ~49 days)
	Handler    HandlerID // ID of handler if invoking a remote handler.
	Op         Op        // Operation. Other fields change based on this value.
	Flags      Flags     // Optional flags.
	Payload    []byte    // Optional payload.
}

// Flags is a set of flags set on a message.
type Flags uint8

	return k[:], err
}

// ParseSSECustomerRequest parses the SSE-C header fields of the provided request.
// It returns the client provided key on success.
func ParseSSECustomerRequest(r *http.Request) (key []byte, err error) {
	return ParseSSECustomerHeader(r.Header)
}

// ParseSSECustomerHeader parses the SSE-C header fields and returns
// the client provided key on success.

		if err := DB.ScanRows(rows, &reusedVar); err != nil {
			t.Errorf("should get no error, but got %v", err)
		}
	}

	if !reflect.DeepEqual(reusedVar, Result{}) {
		t.Errorf("Should find zero values in struct fields, got %+v\n", reusedVar)
	}
}

func TestScanToEmbedded(t *testing.T) {
	person1 := Person{Name: "person 1"}
	person2 := Person{Name: "person 2"}
	DB.Save(&person1).Save(&person2)

### Validation { #validation }

* Validation for most (or all?) Python **data types**, including:
    * JSON objects (`dict`).
    * JSON array (`list`) defining item types.
    * String (`str`) fields, defining min and max lengths.
    * Numbers (`int`, `float`) with min and max values, etc.

* Validation for more exotic types, like:
    * URL.
    * Email.
    * UUID.
    * ...and others.

    <exportedPackage>org.codehaus.plexus.classworlds</exportedPackage>

    <!-- classworlds (for legacy code) -->
    <exportedPackage>org.codehaus.classworlds</exportedPackage>

    <!-- plexus-utils (for DOM-type fields in maven-model) -->
    <exportedPackage>org.codehaus.plexus.util.xml.Xpp3Dom</exportedPackage>
    <exportedPackage>org.codehaus.plexus.util.xml.Xpp3DomBuilder</exportedPackage>

		Async              bool   `json:"async"`
		MaxPubAcksInflight int    `json:"maxPubAcksInflight"`
	} `json:"streaming"`

	RootCAs *x509.CertPool `json:"-"`
}

// Validate NATSArgs fields
func (n NATSArgs) Validate() error {
	if !n.Enable {
		return nil
	}

	if n.Address.IsEmpty() {
		return errors.New("empty address")
	}

	if n.Subject == "" {

    private static final String CONVERSION_ERROR = "Cannot convert: \"%s\" to: %s";

    // ----------------------------------------------------------------------
    // Implementation fields
    // ----------------------------------------------------------------------

    private final Collection<TypeConverterBinding> typeConverterBindings;

/// tip

Pydantic 是 FastAPI 中所有数据验证和序列化的核心，当你在没有设默认值的情况下使用 `Optional` 或 `Union[Something, None]` 时，它具有特殊行为，你可以在 Pydantic 文档中阅读有关<a href="https://docs.pydantic.dev/latest/concepts/models/#required-optional-fields" class="external-link" target="_blank">必需可选字段</a>的更多信息。

///

## 查询参数列表 / 多个值

当你使用 `Query` 显式地定义查询参数时，你还可以声明它去接收一组值，或换句话来说，接收多个值。

例如，要声明一个可在 URL 中出现多次的查询参数 `q`，你可以这样写：