test.py

class Solution:
    def subsets(self, nums: List[int]) -> List[List[int]]:
        res = []

        self.dfs(res, nums)

        return res

    def dfs(self, res, nums, list = [], index = 0):
        if index == len(nums):
            print(list)
            res.append(list)
            return

        self.dfs(res, nums, list, index + 1)

        list.append(nums[index])
        self.dfs(res, nums, list, index + 1)

        list.pop()