code: def make_type_consistent(s1, s2):
      
      if isinstance(s1, str) and isinstance(s2, str):
          return s1, s2
  
      elif isinstance(s1, unicode) and isinstance(s2, unicode):
          return s1, s2
  
      else:
          return unicode(s1), unicode(s2)
docs: If both objects aren't either both string or unicode instances force them to unicode