python 构建二维数组

得这样

input_image = [[] for i in range(28)]for i in range(0,28):    for j in range(0,28):        input_image[i].append(0)

然后在上面画个菱形

for i in range(0,21):  for j in range(0,21):    if (i-j)==-10:        input_image[i][j]=1    if (i+j)==30:        input_image[i][j]=1    if (i+j)==10:        input_image[i][j]=1    if (i-j)==10:        input_image[i][j]=1