human
Solve the following python programming problem given the following code:
def _prepareSinkStack(self) : 
    self.sink_stack = MockSinkStack () 
    def save_message(sink_stack, context, stream, msg) : 
        self.return_message = msg 
        self.return_stream = stream 
terminator_sink = MockSink ({ 
        SinkProperties.Endpoint : None, 
}) 
    terminator_sink.ProcessResponse = self 
    self.sink_stack.Push (terminator_sink) 

    
    

    Fix the buggy line: terminator_sink.ProcessResponse = self
assistant
#Here is Python code to fix the buggy line: terminator_sink.

terminator_sink.ProcessResponse = def save_message(