例如，你可以建立一個名為 `main.py` 的檔案，其中包含以下內容：

```Python hl_lines="3"
import os

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

/// tip

第二個參數是 <a href="https://docs.python.org/zh-tw/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的預設回傳值。

如果沒有提供，預設值為 `None`，這裡我們提供 `"World"` 作為預設值。

///

然後你可以呼叫這個 Python 程式：

    fi
fi

if [ "$REMOVE_USER_AND_GROUP" = "true" ]; then
    if id "$FESS_USER" > /dev/null 2>&1 ; then
        userdel "$FESS_USER"
    fi

    if getent group "$FESS_GROUP" > /dev/null 2>&1 ; then
        groupdel "$FESS_GROUP"
    fi
fi

Ví dụ, bạn có một file `main.py` với:

```Python hl_lines="3"
import os

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

/// tip

Tham số thứ hai cho <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> là giá trị mặc định để trả về.

	if err != nil {
		logger.FatalIf(err, "Unable to validate passed arguments in %s:%s",
			config.EnvArgs, os.Getenv(config.EnvArgs))
	}
	if v == "" {
		v, _, _, err = env.LookupEnv(config.EnvVolumes)
		if err != nil {
			logger.FatalIf(err, "Unable to validate passed arguments in %s:%s",
				config.EnvVolumes, os.Getenv(config.EnvVolumes))
		}
	}
	if v == "" {
		// Fall back to older environment value MINIO_ENDPOINTS

                in.close();
            }
        } catch (final IOException ioe) {
            if (LogStream.level > 0) {
                ioe.printStackTrace(log);
            }
        }

        level = Config.getInt("jcifs.smb1.util.loglevel", -1);
        if (level != -1) {
            LogStream.setLevel(level);
        }

        try {
            "".getBytes(DEFAULT_OEM_ENCODING);

🖼 👆 💪 ✔️ 📁 `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"` 🔢 💲 ⚙️.

///

⤴️ 👆 💪 🤙 👈 🐍 📋:

 *   INSTANCE;
 *   public void funnel(Person person, PrimitiveSink into) {
 *     into.putUnencodedChars(person.getFirstName())
 *         .putUnencodedChars(person.getLastName())
 *         .putInt(person.getAge());
 *   }
 * }
 * }
 *
 * @author Dimitris Andreou
 * @since 11.0
 */
@Beta
@DoNotMock("Implement with a lambda")
public interface Funnel<T extends @Nullable Object> extends Serializable {

  /**

    private int getStatus(NetShareEnumResponse response) throws Exception {
        Field field = getSuperclassField(response.getClass(), "status");
        field.setAccessible(true);
        return field.getInt(response);
    }

    private void setStatus(NetShareEnumResponse response, int value) throws Exception {
        Method method = getSuperclassMethod(response.getClass(), "setStatus", int.class);

    private int getSearchAttributes(SmbComDelete smbComDelete) {
        try {
            Field field = smbComDelete.getClass().getDeclaredField("searchAttributes");
            field.setAccessible(true);
            return field.getInt(smbComDelete);
        } catch (Exception e) {
            throw new RuntimeException("Failed to get searchAttributes field", e);
        }
    }

     *
     * @return the application type string, or empty string if not set
     */
    public static String getAppType() {
        final String appType = System.getenv(FESS_APP_TYPE);
        if (StringUtil.isNotBlank(appType)) {
            return appType;
        }
        return StringUtil.EMPTY;
    }

    /**