subsets

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

        num_set = set(nums)
        res_set = {(),tuple(nums)}

        def recurse(n_set):
            if len(n_set)==1:
                res_set.add(tuple(n_set))

            for num in n_set:
                if tuple(n_set-{(num)}) not in res_set:
                    recurse(n_set-{(num)})
                res_set.add(tuple(n_set-{(num)}))
        recurse(num_set)
        res = []
        for n in res_set:
            res.append(list(n))

        return res