Python 2 beginner friendly approaches
Method 1\n\nclass Solution:\n    def intersection(self, nums: List[List[int]]) -> List[int]:\n        res = []\n        concat = []\n        for i in range(len(
### Method 1\n```\nclass Solution:\n    def intersection(self, nums: List[List[int]]) -> List[int]:\n        res = []\n        concat = []\n        for i in range(len(nums)):\n            concat += nums[i]\n        for i in set(concat):\n            if concat.count(i) == len(nums):\n                res.append(i)\n        return sorted(res)\n```\n\n### Method 2\n```\nclass Solution:\n    def intersection(self, nums: List[List[int]]) -> List[int]:\n        res = []\n        nums = sorted(nums, key=len)\n        check = 0\n        for i in nums[0]:\n            for j in nums:\n                if i in j:\n                    check += 1\n            if check == len(nums):\n                res.append(i)\n            check = 0\n        return sorted(res)\n```
['Python', 'Python3']