```python
from typing import Optional


def say_hi(name: Optional[str]):
    print(f"Hey {name}!")
```

`name` parametresi `Optional[str]` olarak tanımlıdır; ancak isteğe bağlı değildir, parametre olmadan fonksiyonu çağıramazsınız:

```Python
say_hi()  # Ah hayır, bu hata fırlatır! 😱
```

     * @return an {@link Optional} containing the list of profile names to activate, or empty if not specified
     */
    @Nonnull
    Optional<List<String>> activatedProfiles();

    /**
     * Indicates whether Maven should suppress SNAPSHOT updates.
     *
     * @return an {@link Optional} containing true if SNAPSHOT updates should be suppressed, false if not, or empty if not specified
     */
    @Nonnull

			Optional:    true,
			Type:        "string",
			Sensitive:   false,
		},
		config.HelpKV{
			Key:         LookupBindDN,
			Description: `DN for LDAP read-only service account used to perform DN and group lookups` + defaultHelpPostfix(LookupBindDN),
			Optional:    true,
			Type:        "string",
			Sensitive:   true,
		},
		config.HelpKV{

            return Optional.of(Boolean.TRUE);
        }
        return Optional.empty();
    }

    @Override
    public Optional<Boolean> showVersion() {
        if (commandLine.hasOption(CLIManager.SHOW_VERSION)) {
            return Optional.of(Boolean.TRUE);
        }
        return Optional.empty();
    }

    @Override
    public Optional<Boolean> quiet() {

			Optional:    true,
			Type:        "string",
		},
		config.HelpKV{
			Key:         ClaimName,
			Description: `JWT canned policy claim name` + defaultHelpPostfix(ClaimName),
			Optional:    true,
			Type:        "string",
		},
		config.HelpKV{
			Key:         Scopes,

            return Optional.of(Boolean.TRUE);
        }
        return Optional.empty();
    }

    @Override
    @Nonnull
    public Optional<Boolean> model() {
        if (commandLine.hasOption(CLIManager.MODEL)) {
            return Optional.of(Boolean.TRUE);
        }
        return Optional.empty();
    }

    @Override
    @Nonnull
    public Optional<Boolean> plugins() {

    throw new IllegalStateException("Optional.get() cannot be called on an absent value");
  }

  @Override
  public T or(T defaultValue) {
    return checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
  }

  @SuppressWarnings("unchecked") // safe covariant cast
  @Override
  public Optional<T> or(Optional<? extends T> secondChoice) {
    return (Optional<T>) checkNotNull(secondChoice);
  }

  @Override
  public T get() {
    return reference;
  }

  @Override
  public T or(T defaultValue) {
    checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
    return reference;
  }

  @Override
  public Optional<T> or(Optional<? extends T> secondChoice) {
    checkNotNull(secondChoice);
    return this;
  }

  @Override
  public T or(Supplier<? extends T> supplier) {

```

У `typing` також є скорочення, щоб оголосити, що щось може бути `None`, - `Optional`.

Ось порада з моєї дуже «суб'єктивної» точки зору:

- 🚨 Уникайте використання `Optional[SomeType]`
- Натомість ✨ **використовуйте `Union[SomeType, None]`** ✨.

```

O `typing` também tem um atalho para declarar que algo pode ser `None`, com `Optional`.

Aqui vai uma dica do meu ponto de vista bem subjetivo:

* 🚨 Evite usar `Optional[SomeType]`
* Em vez disso ✨ use **`Union[SomeType, None]`** ✨.