},
	}

	for testID, tt := range tests {
		rng := rand.New(rand.NewSource(0))
		// Run for a number of times, shuffling the input to ensure that output is consistent.
		for i := range 10 {
			t.Run(fmt.Sprintf("test-%d-%s-run-%d", testID, tt.name, i), func(t *testing.T) {
				if i > 0 {
					rng.Shuffle(len(tt.m), func(i, j int) {
						tt.m[i], tt.m[j] = tt.m[j], tt.m[i]
					})
				}

-size:1.75rem!important}.fs-4{font-size:1.5rem!important}}@media print{.d-print-inline{display:inline!important}.d-print-inline-block{display:inline-block!important}.d-print-block{display:block!important}.d-print-grid{display:grid!important}.d-print-inline-grid{display:inline-grid!important}.d-print-table{display:table!important}.d-print-table-row{display:table-row!important}.d-print-table-cell{display:table-cell!important}.d-print-flex{display:flex!important}.d-print-inline-flex{display:inline-...

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

Im Hintergrund erstellt das `open("./somefile.txt")` ein Objekt, das als „Kontextmanager“ bezeichnet wird.

////

## Pythonで環境変数を読み取る

環境変数をPythonの**外側**、ターミナル（や他の方法）で作成し、**Python内で読み取る**こともできます。

例えば、以下のような`main.py`ファイルを用意します:

```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> の第2引数は、デフォルトで返される値を指定します。

				i+1, test.result, got)
		}
	}
}

func BenchmarkGetPartFileWithTrie(b *testing.B) {
	b.ResetTimer()

	entriesTrie := trie.NewTrie()
	for i := 1; i <= 10000; i++ {
		entriesTrie.Insert(fmt.Sprintf("%.5d.8a034f82cb9cb31140d87d3ce2a9ede3.67108864", i))
	}

	for i := 1; i <= 10000; i++ {
		partFile := getPartFile(entriesTrie, i, "8a034f82cb9cb31140d87d3ce2a9ede3")
		if partFile == "" {

# protobuf dependencies ourselves. By default this value is false, but some 
# projects enable it, which we don't want here.
# common --define=use_fast_cpp_protos=true

# Make Bazel print out all options from rc files.
common --announce_rc

# TODO(mihaimaruseac): Document this option or remove if no longer needed
common --define=grpc_no_ares=true

////

### 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。

		if deploymentID != formats[i].ID {
			return nil, fmt.Errorf("all pools must have same deployment ID - expected %s, got %s for pool(%s)", deploymentID, formats[i].ID, humanize.Ordinal(i+1))
		}

		bootstrapTrace(fmt.Sprintf("newErasureSets: initializing %s pool", humanize.Ordinal(i+1)), func() {
			z.serverPools[i], err = newErasureSets(ctx, ep, storageDisks[i], formats[i], commonParityDrives, i)
		})
		if err != nil {
			return nil, err

		}
	}

	// check paging works.
	ag := []string{"a", "b", "c", "d", "e", "f", "g"}
	checkObjCount := make(map[string]int)
	for i := range 7 {
		dirName := strings.Repeat(ag[i], 3)
		key := fmt.Sprintf("testPrefix/%s/obj%s", dirName, dirName)
		checkObjCount[key]++
		_, err = obj.PutObject(context.Background(), "bucket", key, mustGetPutObjReader(t, bytes.NewBufferString(uploadContent), int64(len(uploadContent)), "", ""), opts)

se(); err != nil { log.Fatal(err) } for _, c := range curves { p := strings.ToLower(c.P) elementLen := (c.Params.BitSize + 7) / 8 B := fmt.Sprintf("%#v", c.Params.B.FillBytes(make([]byte, elementLen))) Gx := fmt.Sprintf("%#v", c.Params.Gx.FillBytes(make([]byte, elementLen))) Gy := fmt.Sprintf("%#v", c.Params.Gy.FillBytes(make([]byte, elementLen))) log.Printf("Generating %s.go...", p) f, err := os.Create(p + ".go") if err != nil { log.Fatal(err) } defer f.Close() buf := &bytes.Buffer{} if err := t.Execute(buf,...