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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _read_response(self):
 """ Internal response reader. :return: CliResponse or None """

        try:
            line = self.readline()
        except RuntimeError:
            Dut._logger.warning("Failed to read PIPE", extra={'type': '!<-'})
            return -1
        if line:
            if self.store_traces:
                self.traces.append(line)
                self.response_traces.append(line)
            EventObject(EventTypes.DUT_LINE_RECEIVED, self, line)
            match = re.search(r"^\[([\w\W]{4})\]\[([\W\w]{4,}?)\]\: (.*)", line)
            if match:
                self.logger.debug(line, extra={'type': '<<<'})
            else:
                self.logger.info(line, extra={'type': '<--'})

            retcode = self.check_retcode(line)
            if retcode is not None:
                resp = CliResponse()
                resp.retcode = retcode
                resp.traces = self.response_traces
                resp.lines = self.response_traces
                self.response_traces = []
                return resp
        return None