Array Power set problem #Given a set of distinct integers, nums, return all possible subsets (the power set). #Note: The solution set must not contain duplicate subsets. #Example: #Input: nums = [1,2,3] #Output: #[[3],[1],[2],[1,2,3],[1,3],[2,3],[1,2],[]] nums = [ 1 , 2 , 3 ] def subsets1 (nums) : if len (nums)== 0 : return [] if len (nums)== 1 : return [nums,[]] subsets = [[]] for num in nums: subsets += [[num] + lst for lst in subsets] return subsets print (subsets1(nums)) #trace #>>> sub = [[]] #>>> sub += [[1] + lst for lst in sub] #>>> sub #[[], [1]] #>>> sub += [[2] + lst for lst in sub] #>>> sub #[[], [1], [2], [2, 1]] #>>> sub += [[3] + lst for lst in sub] #>>> sub #[[], [1], [2], [2, 1], [3], [3, 1], [3, 2], [3, 2, 1]] #>> For example, let us say we only have the empty set {}. What happens to...