python 类中定义类

class MyClass:
    def __init__(self, name):
        self.name = name

    def say_hello(self):
        print(f"Hello, {self.name}!")

my_instance = MyClass("Alice")
my_instance.say_hello()  # 输出: Hello, Alice!

class MySubClass(MyClass):
    def say_goodbye(self):
        print(f"Goodbye, {self.name}!")

sub_instance = MySubClass("Bob")
sub_instance.say_hello()    # 输出: Hello, Bob!
sub_instance.say_goodbye()  # 输出: Goodbye, Bob!

class MyClass:
    def __init__(self, name):
        self.__name = name  # 私有属性

    def __private_method(self):  # 私有方法
        print("This is a private method.")

    def public_method(self):
        self.__private_method()

def my_decorator(cls):
    class NewClass(cls):
        def new_method(self):
            print("New method added!")
    return NewClass

@my_decorator
class MyClass:
    def __init__(self, name):
        self.name = name

    def say_hello(self):
        print(f"Hello, {self.name}!")

my_instance = MyClass("Charlie")
my_instance.say_hello()  # 输出: Hello, Charlie!
my_instance.new_method()  # 输出: New method added!