new_contents: class Solution(object):
      def findSubsequences(self, nums):
          """
          :type nums: List[int]
          :rtype: List[List[int]]
          """
          lnums = len(nums)
          def dfs(idx, cur):
              if idx == lnums:
                  if len(cur) > 1:
                      yield tuple(cur)
              else:
                  for x in dfs(idx + 1, cur):
                      yield x
                  if not cur or nums[idx] >= cur[-1]:
                      cur.append(nums[idx])
                      for x in dfs(idx + 1, cur):
                          yield x
                      cur.pop()
          return map(list, set(dfs(0, [])))
  
subject: Add py solution for 491. Increasing Subsequences