增加一个python
# 和计算三数之和思路一样，双指针 
        nums.sort()
        n = len(nums) 
        min_sum = float('inf')
        res = 0
        for i in range(n):
            left, right = i+1, n-1 
            while left < right:
                temp = nums[i] + nums[left] + nums[right]
                if temp == target:
                    return temp 
                elif temp > target:
                    right -= 1
                else:
                    left += 1
                if abs(temp - target) < min_sum:
                    min_sum = abs(temp - target)
                    res = temp
        return res