一文掌握Python描述符与装饰器的神奇妙用

class CallableExample:
    def __call__(self, x, y):
        return x + y

# 创建一个可调用的实例
addition = CallableExample()

# 调用该实例
result = addition(3, 5)
print(result)  # 输出：8

def outer_function(x):
    def inner_function(y):
        return x + y
    return inner_function

add_5 = outer_function(5)
result = add_5(3)
print(result)  # 输出：8

class DescriptorExample:
    def __init__(self, initial_value=None):
        self.value = initial_value

    def __get__(self, instance, owner):
        return self.value

    def __set__(self, instance, value):
        self.value = value

class MyClass:
    descriptor = DescriptorExample()

# 使用描述符
obj = MyClass()
obj.descriptor = 42
print(obj.descriptor)  # 输出：42

def my_decorator(func):
    def wrapper(*args, **kwargs):
        print("Before the method is called")
        result = func(*args, **kwargs)
        print("After the method is called")
        return result
    return wrapper

class MyClass:
    @my_decorator
    def some_method(self, x, y):
        return x + y

# 使用装饰器装饰类方法
obj = MyClass()
result = obj.some_method(3, 5)
print(result)  # 输出：8