code: def python_2_unicode_compatible(klass):
      
      if sys.version_info[0] == 2:
          klass.__unicode__ = klass.__str__
          klass.__str__ = lambda self: self.__unicode__().encode('utf-8')
      return klass
docs: A decorator that defines __unicode__ and __str__ methods under Python 2.
      Under Python 3 it does nothing.
      To support Python 2 and 3 with a single code base, define a __str__ method
      returning text and apply this decorator to the class.