matplotlib.pyplot的imshow无法显示图片

最近写yolo算法的时候发现matplotlib.pyplot的imshow无法显示图片，代码如下

def db_visualize(db):
    imgs, imgs_boxes = next(iter(db))
    img, img_boxes = imgs[0], imgs_boxes[0]

    f,ax1 = plt.subplots(1,figsize=(10,10))
    # display the image, [512,512,3]
    ax1.imshow(img)
    for x1,y1,x2,y2,l in img_boxes: # [40,5]
        x1,y1,x2,y2 = float(x1), float(y1), float(x2), float(y2)
        w = x2 - x1
        h = y2 - y1

        if l==1: # green for sugarweet
            color = (0,1,0)
        elif l==2: # red for weed
            color = (1,0,0) # (R,G,B)
        else: # ignore invalid boxes
            break

        rect = patches.Rectangle((x1,y1), w, h, linewidth=2,edgecolor=color, facecolor='none')
        ax1.add_patch(rect)

添加plt.show() 编辑器会闪退
后来尝试import pylab 用pylab.show() 搞定
修改后的如下

import pylab
def db_visualize(db):
    # imgs:[b, 512, 512, 3]
    # imgs_boxes: [b, 40, 5]
    imgs, imgs_boxes = next(iter(db))
    img, img_boxes = imgs[0], imgs_boxes[0]

    f,ax1 = plt.subplots(1,figsize=(10,10))
    # display the image, [512,512,3]
    ax1.imshow(img)
    for x1,y1,x2,y2,l in img_boxes: # [40,5]
        x1,y1,x2,y2 = float(x1), float(y1), float(x2), float(y2)
        w = x2 - x1
        h = y2 - y1

        if l==1: # green for sugarweet
            color = (0,1,0)
        elif l==2: # red for weed
            color = (1,0,0) # (R,G,B)
        else: # ignore invalid boxes
            break

        rect = patches.Rectangle((x1,y1), w, h, linewidth=2,edgecolor=color, facecolor='none')
        ax1.add_patch(rect)
    pylab.show()