# BEFORE - Unit test: Column level
def test_get_impress_position(logs):
    impress_events = logs.explode('impressions')
    impress_positions = get_impress_positions(impress_events)

    # Since each impress log has 4 items, expect impression positions to be five sets of 1-4
    pd.testing.assert_series_equal(impress_positions, pd.Series([1, 2, 3, 4] * 5))


# AFTER - Unit test: Column level (updated)
def test_get_impress_position(logs):
    logs = update_impression_col(logs)
    impress_events = logs.explode('impressions')
    impress_positions = get_impress_positions(impress_events)

    # Update impress positions (too brittle?)
    pd.testing.assert_series_equal(impress_positions, pd.Series([1, 2, 3,
                                                                 1, 2,
                                                                 1, 2, 3, 4,
                                                                 1, 2, 3, 4,
                                                                 1, 2]))