defer f.Close()
	dir, err := f.Stat()
	if err != nil {
		t.Fatalf("stat %s: %s", f.Name(), err)
	}

	// Can't change uid unless root, but can try
	// changing the group id. First try our current group.
	gid := Getgid()
	t.Log("gid:", gid)
	if err = Chown(f.Name(), -1, gid); err != nil {
		t.Fatalf("chown %s -1 %d: %s", f.Name(), gid, err)
	}
	sys := dir.Sys().(*syscall.Stat_t)
	checkUidGid(t, f.Name(), int(sys.Uid), gid)

🖼 👆 💪 ✔️ 📁 `main.py` ⏮️:

```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> 🔢 💲 📨.

    🚥 🚫 🚚, ⚫️ `None` 🔢, 📥 👥 🚚 `"World"` 🔢 💲 ⚙️.

⤴️ 👆 💪 🤙 👈 🐍 📋:

        }
        baseDir = new File(layout.getGradleUserHomeDir(), "daemon");
        gradleUserHomeDir = layout.getGradleUserHomeDir();
        envVariables = new HashMap<>(System.getenv());
    }

    public boolean isEnabled() {
        return enabled;
    }

    public void setEnabled(boolean enabled) {
        this.enabled = enabled;
    }

    public File getBaseDir() {

	// connection health check.
	if s := os.Getenv("HTTP2_READ_IDLE_TIMEOUT_SECONDS"); len(s) > 0 {
		i, err := strconv.Atoi(s)
		if err != nil {
			klog.Warningf("Illegal HTTP2_READ_IDLE_TIMEOUT_SECONDS(%q): %v."+
				" Default value %d is used", s, err, ret)
			return ret
		}
		ret = i
	}
	return ret
}

func pingTimeoutSeconds() int {
	ret := 15
	if s := os.Getenv("HTTP2_PING_TIMEOUT_SECONDS"); len(s) > 0 {

// $HOME is not set, falls back to os.TempDir().
func setTmpDir(ui plugin.UI) (string, error) {
	var dirs []string
	if profileDir := os.Getenv("PPROF_TMPDIR"); profileDir != "" {
		dirs = append(dirs, profileDir)
	}
	if homeDir := os.Getenv(homeEnv()); homeDir != "" {
		dirs = append(dirs, filepath.Join(homeDir, "pprof"))
	}
	dirs = append(dirs, os.TempDir())
	for _, tmpDir := range dirs {

	euid = int(r0)
	return
}

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

func Getgid() (gid int) {
	r0, _ := C.getgid()
	gid = int(r0)
	return
}

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

func Getuid() (uid int) {
	r0, _ := C.getuid()
	uid = int(r0)
	return
}

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

		return
	}

	// Interpret GOTOOLCHAIN to select the Go toolchain to run.
	gotoolchain := cfg.Getenv("GOTOOLCHAIN")
	gover.Startup.GOTOOLCHAIN = gotoolchain
	if gotoolchain == "" {
		// cfg.Getenv should fall back to $GOROOT/go.env,
		// so this should not happen, unless a packager
		// has deleted the GOTOOLCHAIN line from go.env.

// involving the testing harness.
func init() {
	if os.Getenv("GO_TEST_RUNTIME_PANIC") == "1" {
		defer func() {
			if r := recover(); r != nil {
				// We expect to crash, so exit 0
				// to indicate failure.
				os.Exit(0)
			}
		}()
		runtime.PanicForTesting(nil, 1)
		// We expect to crash, so exit 0 to indicate failure.
		os.Exit(0)
	}
	if os.Getenv("GO_TEST_RUNTIME_NPE_READMEMSTATS") == "1" {

		t.Fatalf("Fchmodat: unexpected error: %v, expected EOPNOTSUPP", err)
	}
}

func TestMain(m *testing.M) {
	if os.Getenv("GO_DEATHSIG_PARENT") == "1" {
		deathSignalParent()
	} else if os.Getenv("GO_DEATHSIG_CHILD") == "1" {
		deathSignalChild()
	} else if os.Getenv("GO_SYSCALL_NOERROR") == "1" {
		syscallNoError()
	}

	os.Exit(m.Run())
}

func TestParseNetlinkMessage(t *testing.T) {

  // staleness (seconds) if provided.
  const char* block_size_env = std::getenv(kBlockSize);
  if (block_size_env && absl::SimpleAtoi(block_size_env, &value)) {
    block_size = value * 1024 * 1024;
  }
  const char* max_bytes_env = std::getenv(kMaxCacheSize);
  if (max_bytes_env && absl::SimpleAtoi(max_bytes_env, &value)) {
    max_bytes = static_cast<size_t>(value * 1024 * 1024);