new_contents: def verifyUnique(string):
      if len(string) > 128:
          return False
      characterHash = [0] * 128
      for character in string:
          hashKey = ord(character)%128
          if(characterHash[hashKey] > 0):
              return False
          else:
              characterHash[hashKey] = characterHash[hashKey]+1
      return True
  
  
  print verifyUnique('test') # False ,O(n)
  print verifyUnique('aquickboASDFwnfxjmps><verthlzydg')  # True ,O(n)
  
subject: Verify the given string has unique characters