new_contents: class Solution:
      # @return a tuple, (index1, index2)
  
      def twoSum(self, num, target):
          pos = {n: i for i, n in enumerate(num)}
          for i, n in enumerate(num):
              if target-n in pos and pos[target-n] > i:
                  return i+1, pos[target-n]+1
  
subject: add solution for Two Sum