code: def immutable(function):
      '''Add the instance internal state as the second parameter
      of the decorated function.'''
  
      def wrapper(self, *args, **kwargs):
          state = freeze(self._get_state())
          return function(self, state, *args, **kwargs)
  
      return wrappef immutable(function):
      '''Add the instance internal state as the second parameter
      of the decorated function.'''
  
      def wrapper(self, *args, **kwargs):
          state = freeze(self._get_state())
          return function(self, state, *args, **kwargs)
  
      return wrapper
docs: Add the instance internal state as the second parameter
      of the decorated function.