为什么不能将类属性作为参数直接赋值给类括号，而要使用def __init__方法呢？

class MyClass:
    class_attribute = "I am a class attribute"

    def __init__(self, instance_attribute):
        self.instance_attribute = instance_attribute

# 创建实例
obj1 = MyClass("Instance attribute for obj1")
obj2 = MyClass("Instance attribute for obj2")

# 访问类属性
print(MyClass.class_attribute)  # 输出: I am a class attribute
print(obj1.class_attribute)     # 输出: I am a class attribute
print(obj2.class_attribute)     # 输出: I am a class attribute

# 访问实例属性
print(obj1.instance_attribute)  # 输出: Instance attribute for obj1
print(obj2.instance_attribute)  # 输出: Instance attribute for obj2

class MyClass:
    pass

# 设置类属性
MyClass.class_attribute = "I am a class attribute"