Three sum algorithm solution

Question

Original Problem Statement:

Given an array S of n integers, are there elements a, b, C in S such that a + b + c = 0? Find all unique triplets in the array which gives

Answer 1

I'd like to add the answer you claimed(in the comment) to post:

class Solution(object):
    def threeSum(self, nums):
        """
        :type nums: List[int]
        :rtype: List[List[int]]
        """
        def twoSum(self, nums, target):
            targ = target
            for index, i in enumerate(nums):
                targ -= i

                # if targ in nums[index+1:]:
                #    return [nums[index], nums[nums[index+1:].index(targ)+index+1]]
                _num = nums[:index] + nums[index+1:]
                if targ in _num: 
                    return [i, targ]
                else:
                    targ = target
            return None
        res = []
        for index, i in enumerate(nums):
            target = i * -1
            num = nums[:index] + nums [index+1:]
            ans = twoSum(self, num, target)
            if ans != None:
                temp = ans + [i]
                temp.sort()
                res.append(temp)
        print(res)
        import itertools
        res.sort()
        res = list(res for res,_ in itertools.groupby(res))
        return res

I have only run it my brain and hope it is right.