<pre>
var a []int
var c, c1, c2, c3, c4 chan int
var i1, i2 int
select {
case i1 = &lt;-c1:
	print("received ", i1, " from c1\n")
case c2 &lt;- i2:
	print("sent ", i2, " to c2\n")
case i3, ok := (&lt;-c3):  // same as: i3, ok := &lt;-c3
	if ok {
		print("received ", i3, " from c3\n")
	} else {
		print("c3 is closed\n")
	}
case a[f()] = &lt;-c4:
	// same as:
	// case t := &lt;-c4
	//	a[f()] = t

!important;\n    display: inline-flex !important;\n  }\n}\n\n@media print {\n  .d-print-none {\n    display: none !important;\n  }\n  .d-print-inline {\n    display: inline !important;\n  }\n  .d-print-inline-block {\n    display: inline-block !important;\n  }\n  .d-print-block {\n    display: block !important;\n  }\n  .d-print-table {\n    display: table !important;\n  }\n  .d-print-table-row {\n    display: table-row !important;\n  }\n  .d-print-table-cell {\n    display: table-cell !important;\n  }\n  .d-print-flex...

デフォルトの例外ハンドラを`fastapi.exception_handlers`からインポートして再利用することができます:

```Python hl_lines="2 3 4 5 15 21"
{!../../docs_src/handling_errors/tutorial006.py!}
```

この例では、非常に表現力のあるメッセージでエラーを`print`しています。

////

### 在 Python 中读取环境变量

您还可以在 Python 之外的地方（例如终端中或使用任何其他方法）创建环境变量，然后在 Python 中读取它们。

例如，您可以有一个名为 `main.py` 的文件，其中包含以下内容：

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

<a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的第二个参数是要返回的默认值。

		consoleapi.TLSPort = globalMinioConsolePort
		consoleapi.Hostname = globalMinioConsoleHost
	}

	return server, nil
}

// Check for updates and print a notification message
func checkUpdate(mode string) {
	updateURL := minioReleaseInfoURL
	if runtime.GOOS == globalWindowsOSName {
		updateURL = minioReleaseWindowsInfoURL
	}

	u, err := url.Parse(updateURL)

        @Override
        public String getAsString(final Object value) {
            if (value instanceof Date) {
                return DEFAULT_DATE_PRINTER.print(((Date) value).getTime());
            }
            return null;
        }

        @Override
        public Object getAsObject(final String value) {
            if (StringUtil.isEmpty(value)) {

	for i := 0; i < b.N; i++ {
		testZip64(b, 1<<26)
	}
}

func BenchmarkZip64TestSizes(b *testing.B) {
	for _, size := range []int64{1 << 12, 1 << 20, 1 << 26} {
		b.Run(fmt.Sprint(size), func(b *testing.B) {
			b.RunParallel(func(pb *testing.PB) {
				for pb.Next() {
					testZip64(b, size)
				}
			})
		})
	}
}

func TestSuffixSaver(t *testing.T) {
	const keep = 10

	we := wg.Spec.Template
	ports := []string{}
	for _, v := range we.Ports {
		ports = append(ports, fmt.Sprint(v))
	}
	// respect the inbound port annotation and capture all traffic if no inbound ports are set
	portBehavior := "*"
	if len(ports) > 0 {
		portBehavior = strings.Join(ports, ",")
	}

}

var bmbuf []byte

func valName(x int) string {
	if s := x >> 20; s<<20 == x {
		return fmt.Sprintf("%dM", s)
	}
	if s := x >> 10; s<<10 == x {
		return fmt.Sprintf("%dK", s)
	}
	return fmt.Sprint(x)
}

func benchBytes(b *testing.B, sizes []int, f func(b *testing.B, n int)) {
	for _, n := range sizes {
		if isRaceBuilder && n > 4<<10 {
			continue
		}
		b.Run(valName(n), func(b *testing.B) {

                    }
                }
                buf.append('}');
                buf.append('\n');
                try {
                    response.getWriter().print(buf.toString());
                } catch (final IOException e) {
                    throw new IORuntimeException(e);
                }
                return true;
            }, OptionalThing.empty());