def test_unique_parallel(self):
        # TODO: test without file
        def test_impl():
            df = pq.read_table('example.parquet').to_pandas()
            return (df.four.unique() == 3.0).sum()

        hpat_func = self.jit(test_impl)
        self.assertEqual(hpat_func(), test_impl())
        self.assertEqual(count_array_REPs(), 0)