예를 들어, 어떤 값이 `str` 또는 `None`이 될 수 있다고 선언할 수 있습니다:

```python
from typing import Union


def say_hi(name: Union[str, None]):
        print(f"Hi {name}!")
```

`typing`에는 `None`이 될 수 있음을 선언하는 축약형으로 `Optional`도 있습니다.

아주 개인적인 관점에서의 팁입니다:

- 🚨 `Optional[SomeType]` 사용은 피하세요
- 대신 ✨ **`Union[SomeType, None]`를 사용하세요** ✨.

		Can be repeated to define multiple symbols.
	-I dir1 -I dir2
		Search for #include files in dir1, dir2, etc,
		after consulting $GOROOT/pkg/$GOOS_$GOARCH.
	-S
		Print assembly and machine code.
	-V
		Print assembler version and exit.
	-debug
		Dump instructions as they are parsed.
	-dynlink
		Support references to Go symbols defined in other shared libraries.
	-e

# Code blocks { #code-blocks }

Some text

```python
# This is a sample Python code block
def hello_world():
    # Comment with indentation
    print("Hello, world!")  # Print greeting
```

Some more text

```toml
# This is a sample TOML code block
title = "TOML Example"  # Title of the document
```

And more text

```console
// Use the command "live" and pass the language code as a CLI argument

# Code blocks { #code-blocks }

Some text

```python
# This is a sample Python code block
def hello_world():
    # Comment with indentation
    print("Hello, world!")  # Print greeting
```

Some more text

```toml
# This is a sample TOML code block
title = "TOML Example"  # Title of the document
```

Extra code block

```
$ cd my_project
```

And more text

```console

 * </ul>
 *
 * <h2>Usage Example</h2>
 *
 * <pre>
 * {@code
 * Session session = ... // Obtain a Maven session
 * Packaging packaging = session.requirePackaging("jar");
 * System.out.println(packaging.getId()); // Outputs "jar"
 * }
 * </pre>
 *
 * @see org.apache.maven.api.Session#requirePackaging(String)
 * @see org.apache.maven.api.Project#getPackaging()

#
# // The list may change at any time, regenerated with:
# for (String pkg : new TreeSet<>(Arrays.asList(
#                       Security.getProperty("package.access").split(",")))) {
#   System.out.println(pkg + "**");
# }
#
@defaultMessage non-public internal runtime class
com.oracle.webservices.internal.**
com.oracle.xmlns.internal.**
com.sun.activation.registries.**
com.sun.browser.**
com.sun.corba.se.**

    /**
     * @throws Exception
     */
    public void testEncode() throws Exception {
        assertEquals("1", ENCODED_DATA, Base64Util.encode(BINARY_DATA));
        System.out.println(Base64Util.encode(new byte[] { 'a', 'b', 'c' }));
    }

    /**
     * @throws Exception
     */
    public void testDecode() throws Exception {
        final byte[] decodedData = Base64Util.decode(ENCODED_DATA);

                for (ModelProblem problem : modelBuildingException.getProblems()) {
                    message.append(problem).append("\n");
                }
                System.out.println(message);
                fail(message.toString());
            }

            throw e;
        }
    }

    protected MavenProject getProject(File pom) throws Exception {

        activityHelper.print("aaa", OptionalThing.empty(), Map.of());
        assertEquals("action:AAA\tuser:-", localLogMsg.get());

        activityHelper.print("aaa bbb", createUser("testuser", new String[0]), Map.of("111", "222"));
        assertEquals("action:AAA BBB\tuser:testuser\t111:222", localLogMsg.get());

```python
#Объявление функции
def hello_world():# Печать приветствия
    print("Hello, world!")  #Печать приветствия без пробела после решётки
```

```console
//Объявление функции
def hello_world():// Печать приветствия
    print("Hello, world!")  //Печать приветствия без пробела после слешей
```