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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, test_file, save_dir=None, logger=None, num_buckets_test=10, test_batch_size=5000):
 """Run evaluation on test set Parameters test_file : str path to test set save_dir : str where to store intermediate results and log logger : logging.logger logger for printing results num_buckets_test : int number of clusters for sentences from test set test_batch_size : int batch size of test set Returns ------- tuple UAS, LAS """

        parser = self._parser
        vocab = self._vocab
        with mx.Context(mxnet_prefer_gpu()):
            UAS, LAS, speed = evaluate_official_script(parser, vocab, num_buckets_test, test_batch_size,
                                                       test_file, os.path.join(save_dir, 'valid_tmp'))
        if logger is None:
            logger = init_logger(save_dir, 'test.log')
        logger.info('Test: UAS %.2f%% LAS %.2f%% %d sents/s' % (UAS, LAS, speed))

        return UAS, LAS