```

## 声明类型

你刚刚看到的就是声明类型提示的主要场景。用于函数的参数。

这也是你将在 **FastAPI** 中使用它们的主要场景。

### 简单类型

不只是 `str`，你能够声明所有的标准 Python 类型。

比如以下类型：

* `int`
* `float`
* `bool`
* `bytes`

```Python hl_lines="1"
{!../../docs_src/python_types/tutorial005.py!}
```

### 嵌套类型

有些容器数据结构可以包含其他的值，比如 `dict`、`list`、`set` 和 `tuple`。它们内部的值也会拥有自己的类型。

你可以使用 Python 的 `typing` 标准库来声明这些类型以及子类型。

// AppendTo will append the checksum to b.
// 'parts' is used when checksum has ChecksumMultipart set.
// ReadCheckSums reads the values back.
func (c *Checksum) AppendTo(b []byte, parts []byte) []byte {
	if c == nil {
		return nil
	}
	var tmp [binary.MaxVarintLen32]byte
	n := binary.PutUvarint(tmp[:], uint64(c.Type))
	crc := c.Raw
	if c.Type.Trailing() {
		// When we serialize we don't care if it was trailing.

}

// UUIDHash - use uuid to make md5sum
type UUIDHash struct {
	uuid []byte
}

// Write -  implement hash.Hash Write
func (u UUIDHash) Write(p []byte) (n int, err error) {
	return len(p), nil
}

// Sum -  implement md5.Sum
func (u UUIDHash) Sum(b []byte) []byte {
	return u.uuid
}

// Reset -  implement hash.Hash Reset
func (u UUIDHash) Reset() {
	return
}

pkg archive/zip, method (*Writer) SetOffset(int64)
pkg bufio, method (*Reader) Discard(int) (int, error)
pkg bufio, method (ReadWriter) Discard(int) (int, error)
pkg bytes, func LastIndexByte([]uint8, uint8) int
pkg bytes, method (*Buffer) Cap() int
pkg bytes, method (*Reader) Size() int64
pkg crypto, const SHA512_224 = 14
pkg crypto, const SHA512_224 Hash
pkg crypto, const SHA512_256 = 15
pkg crypto, const SHA512_256 Hash

    byte[] b;
    int off, dataCompactionMode, dataLength, dataOffset;

    SmbComReadAndXResponse() {
    }
    SmbComReadAndXResponse( byte[] b, int off ) {
        this.b = b;
        this.off = off;
    }

    void setParam( byte[] b, int off ) {
        this.b = b;
        this.off = off;
    }
    int writeParameterWordsWireFormat( byte[] dst, int dstIndex ) {
        return 0;

    /**
     * 
     */
    public static final byte SMB2_OPLOCK_LEVEL_NONE = 0x0;
    /**
     * 
     */
    public static final byte SMB2_OPLOCK_LEVEL_II = 0x1;
    /**
     * 
     */
    public static final byte SMB2_OPLOCK_LEVEL_EXCLUSIVE = 0x8;
    /**
     * 
     */
    public static final byte SMB2_OPLOCK_LEVEL_BATCH = 0x9;
    /**
     * 
     */

	}
	return 0
}

// asTimedAction returns the element as a madmin.TimedAction.
func (a AccElem) asTimedAction() madmin.TimedAction {
	return madmin.TimedAction{AccTime: uint64(a.Total), Count: uint64(a.N), Bytes: uint64(a.Size)}
}

// lastMinuteLatency keeps track of last minute latency.
type lastMinuteLatency struct {
	Totals  [60]AccElem
	LastSec int64
}

// Merge data of two lastMinuteLatency structure

    /**
     * @param data
     * @return MIC
     * @throws CIFSException
     */
    byte[] calculateMIC ( byte[] data ) throws CIFSException;


    /**
     * @param data
     * @param mic
     * @throws CIFSException
     */
    void verifyMIC ( byte[] data, byte[] mic ) throws CIFSException;


    /**
     * @return whether MIC can be used
     */

import com.google.common.collect.Lists;

public class MemoryUtilTest extends UnitFessTestCase {

    public void test_byteCountToDisplaySize() {
        assertEquals("0bytes", MemoryUtil.byteCountToDisplaySize(0L));
        assertEquals("999bytes", MemoryUtil.byteCountToDisplaySize(999L));
        assertEquals("1000bytes", MemoryUtil.byteCountToDisplaySize(1000L));

	}
}

func TestARNUnmarshalXML(t *testing.T) {
	testCases := []struct {
		data        []byte
		expectedARN *ARN
		expectErr   bool
	}{
		{[]byte("<ARN></ARN>"), nil, true},
		{[]byte("<ARN>arn:minio:sqs:::</ARN>"), nil, true},
		{[]byte("<ARN>arn:minio:sqs::1:webhook</ARN>"), &ARN{TargetID{"1", "webhook"}, ""}, false},
		{[]byte("<ARN>arn:minio:sqs:us-east-1:1:webhook</ARN>"), &ARN{TargetID{"1", "webhook"}, "us-east-1"}, false},
	}