docs: def not_a_string(obj):
      """It's probably not a string, in the sense
      that Python2/3 get confused about these things"""
      my_type = str(type(obj))
      if is_py3():
          is_str = my_type.find('bytes') < 0 and my_type.find('str') < 0
          return is_str
  
      return my_type.find('str') < 0 and \
          my_type.find('unicode') < 0