# 使用 Dataclasses { #using-dataclasses }

FastAPI 建立在 **Pydantic** 之上，我之前示範過如何使用 Pydantic 模型來宣告請求與回應。

但 FastAPI 也同樣支援以相同方式使用 [`dataclasses`](https://docs.python.org/3/library/dataclasses.html)：

{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

這之所以可行，要感謝 **Pydantic**，因為它 [內建支援 `dataclasses`](https://docs.pydantic.dev/latest/concepts/dataclasses/#use-of-stdlib-dataclasses-with-basemodel)。

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"sort"
	"time"

	"github.com/minio/madmin-go/v3"
)

// BucketTargetUsageInfo - bucket target usage info provides

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"context"
)

const (
	bucketReplLastHrFailedBytes                    = "last_hour_failed_bytes"
	bucketReplLastHrFailedCount                    = "last_hour_failed_count"

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"context"
	"runtime"
	"time"

	"github.com/prometheus/procfs"
)

const (
	processLocksReadTotal           = "locks_read_total"

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"runtime/debug"
	"sort"
	"strings"
	"time"
)

const (
	// deadline (in seconds) up to which the go routine leak detection has to be retried.

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package kms

import (
	"context"
	"encoding"
	"encoding/json"
	"strconv"

	jsoniter "github.com/json-iterator/go"
	"github.com/minio/madmin-go/v3"
)

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package deadlineconn

import (
	"bufio"
	"fmt"
	"io"
	"net"
	"sync"
	"testing"
	"time"
)

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package etag

import (
	"context"
	"crypto/md5"
	"fmt"
	"hash"
	"io"
)

// Tagger is the interface that wraps the basic ETag method.
type Tagger interface {
	ETag() ETag
}

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package event

import (
	"crypto/rand"
	"errors"
	"reflect"
	"testing"
	"time"

	"github.com/minio/minio/internal/store"
)

type ExampleTarget struct {
	id       TargetID

 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express