如何使用OpenCV在矩形内绘制九个圆点？

import cv2import numpy as np# 矩形坐标left, top, right, bottom = 530, 836, 685, 885# 创建一个白色画布img = np.ones((1000, 1000), np.uint8) * 255# 绘制矩形边框cv2.rectangle(img, (left, top), (right, bottom), 0)# 求出九个点坐标for y in range(top * 2, bottom * 2 + 1, bottom - top):    for x in range(left * 2, right * 2 + 1, right - left):        cv2.circle(img, (x, y), 8, 0, cv2.FILLED, cv2.LINE_AA, 1)# 显示图像cv2.imshow('img', img)cv2.waitKey()