def display_image(index):
    plt.imshow(images[index].T, cmap = "binary", origin='lower', extent = [0, img_size, 0, img_size])
    for box in bounding_boxes[index]:
        plt.gca().add_patch(Rectangle((box[0], box[1]), box[2], box[3], ec = 'r', fc = 'none'))
    plt.xticks([])
    plt.yticks([])
    plt.show()

display_image(np.random.randint(0, n_images))