def METHOD_NAME(self):
    # Test data.
    idx = np.arange(16)
    arr = np.zeros(16)
    arr2 = np.ones(16)
    data = {"index": arr}
    df = DataFrame(data, index=idx)
    plot_data = DataFramePlotData(data_frame=df)
    assert_array_equal(plot_data.get_data("index"), df["index"].values)
    # Can set 'index' column
    with monitor_events(plot_data) as events:
        plot_data.set_data("index", arr2)
        self.assertEqual(events, [{"changed": ["index"]}])
        assert_array_equal(df["index"].values, arr2)
    # Can remove 'index' column
    with monitor_events(plot_data) as events:
        plot_data.del_data("index")
        self.assertNotIn("index", df.columns)
        # Since there is always an index, this will register a 'changed'
        # event instead of a 'removed' event.
        self.assertEqual(events, [{"changed": ["index"]}])
        assert_array_equal(plot_data.get_data("index"), df.index.values)