javascript中的闭包

JS中的闭包写法跟python的很类似

function lazy_sum(x) {
    var sum = function (y) {
        return x*x+y*10;
    }
    return sum;
}

var f = lazy_sum(1);
f(5);

运行结果是：

function lazy_sum(x) {     var sum = function (y)...     return sum; }  var f = lazy_sum(1); f(5);  
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