class Solution:
    def subsets(self, nums: List[int]) -> List[List[int]]:
        ans=self.helper(nums,0,[],[])
        return ans


    def helper(self,input_chars,index,result,curr_soln):
        if index==len(input_chars):
            #print(curr_soln)
            result.append(curr_soln.copy())
            return

        self.helper(input_chars,index+1,result,curr_soln)
        curr_soln.append(input_chars[index])
        self.helper(input_chars,index+1,result,curr_soln)
        curr_soln.pop()
        return result