从__init__分配属性的快捷方式

class MyClass:
    shared_value = "This is a shared value"

# 访问类变量
print(MyClass.shared_value)  # 输出: This is a shared value

class MyClass:
    def __init__(self):
        self.instance_value = "Initial value"

# 创建实例并访问实例变量
obj = MyClass()
print(obj.instance_value)  # 输出: Initial value

class ParentClass:
    def __init__(self):
        self.parent_attribute = "Parent value"

class ChildClass(ParentClass):
    def __init__(self):
        super().__init__()  # 确保调用父类的构造函数
        self.child_attribute = "Child value"

# 创建子类实例并检查属性
child_obj = ChildClass()
print(child_obj.parent_attribute)  # 输出: Parent value
print(child_obj.child_attribute)   # 输出: Child value