```Python
@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

könnte Ihr Programm so ausgeführt werden:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Funktion ausgeführt

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")

from typing import Optional


def say_hi(name: Optional[str]):

from typing import Union


def say_hi(name: Union[str, None] = None):
    if name is not None:
        print(f"Hey {name}!")
    else:

def say_hi(name: str | None = None):
    if name is not None:
        print(f"Hey {name}!")
    else:

from typing import Optional


def say_hi(name: Optional[str] = None):
    if name is not None:
        print(f"Hey {name}!")
    else:

et: eesti
eu: euskara
fa: فارسی
ff: Fulfulde
fi: suomi
fj: Vakaviti
fo: føroyskt
fr: français
fy: Frysk
ga: Gaeilge
gd: Gàidhlig
gl: galego
gu: ગુજરાતી
gv: Gaelg
ha: هَوُسَ
he: עברית
hi: हिन्दी
ho: Hiri Motu
hr: Hrvatski
ht: Kreyòl ayisyen
hu: magyar
hy: Հայերեն
hz: Otjiherero
ia: Interlingua
id: Bahasa Indonesia
ie: Interlingue
ig: Asụsụ Igbo
ii: ꆈꌠ꒿ Nuosuhxop
ik: Iñupiaq

🖼, 🚥 👆 ✔️ 🔢:

```Python
@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

👆 📋 💪 🛠️ 💖 👉:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Camila")

def say_hi(name: str | None):

```Python
say_hi()  # Oh, no, this throws an error! 😱
```

Tham số `name` **vẫn được yêu cầu** (không phải là *tùy chọn*) vì nó không có giá trị mặc định. Trong khi đó, `name` chấp nhận `None` như là giá trị:

```Python
say_hi(name=None)  # This works, None is valid 🎉
```

{!../../../docs_src/python_types/tutorial009c.py!}
```

🔢 `name` 🔬 `Optional[str]`, ✋️ ⚫️ **🚫 📦**, 👆 🚫🔜 🤙 🔢 🍵 🔢:

```Python
say_hi()  # Oh, no, this throws an error! 😱
```

`name` 🔢 **✔** (🚫 *📦*) ↩️ ⚫️ 🚫 ✔️ 🔢 💲. , `name` 🚫 `None` 💲:

```Python
say_hi(name=None)  # This works, None is valid 🎉
```

👍 📰, 🕐 👆 🔛 🐍 3️⃣.1️⃣0️⃣ 👆 🏆 🚫 ✔️ 😟 🔃 👈, 👆 🔜 💪 🎯 ⚙️ `|` 🔬 🇪🇺 🆎: