def METHOD_NAME(self):
    """Test plotting error map with fake backend v1."""
    backend = FakeKolkata()
    img_ref = path_to_diagram_reference("kolkata_error.png")
    fig = plot_error_map(backend)
    with BytesIO() as img_buffer:
        fig.savefig(img_buffer, format="png")
        img_buffer.seek(0)
        self.assertImagesAreEqual(Image.open(img_buffer), img_ref, 0.2)
    plt.close(fig)