这是在练习过程中遇到的问题，各位大佬看看是怎么回事

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#1 Created at ... [Delete] [Delete and Lock User]

def build(x, y):

return lambda: x * x + y * y

build(2,3)

Out[3]:

<function __main__.build.<locals>.<lambda>()>
r=build(2,3)
print(r)
In [6]:
print(r)
<function build.<locals>.<lambda> at 0x00000124C3F758C8>

#2 Created at ... [Delete] [Delete and Lock User]

因为你 build 函数返回的是一个表达式也就是一个匿名函数，想要结果的话请执行 r()

#3 Created at ... [Delete] [Delete and Lock User]

哇是滴谢谢啦

#4 Created at ... [Delete] [Delete and Lock User]

闭包

#5 Created at ... [Delete] [Delete and Lock User]

好像暂时还不知道闭包是啥意思。。。

#6 Created at ... [Delete] [Delete and Lock User]

print(r)

print(r)就说明了问题：r=build(2,3)只是一个lambda，并没有执行这个lambda

附加一个立即执行就可以了。

r = build(2,3)()
print(r)