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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 evaluate(self, system_id=1, rouge_args=None):
 """ Run ROUGE to evaluate the system summaries in system_dir against the model summaries in model_dir. The summaries are assumed to be in the one-sentence-per-line HTML format ROUGE understands. system_id: Optional system ID which will be printed in ROUGE's output. Returns: Rouge output as string. """

        self.write_config(system_id=system_id)
        options = self.__get_options(rouge_args)
        command = [self._bin_path] + options
        env = None
        if hasattr(self, "_home_dir") and self._home_dir:
            env = {'ROUGE_EVAL_HOME': self._home_dir}
        self.log.info(
            "Running ROUGE with command {}".format(" ".join(command)))
        rouge_output = check_output(command, env=env).decode("UTF-8")
        return rouge_output