之所以会出现此异常，是因为如果没有某些第三方库或您自己的代码来处理硒中的元素，就无法截取它的屏幕快照。

它使用称为PIL的库来执行此操作：

from selenium import webdriver
from PIL import Image

fox = webdriver.Firefox()
fox.get('https://http://codingdict.com/')

# now that we have the preliminary stuff out of the way time to get that image :D
element = fox.find_element_by_id('hlogo') # find part of the page you want image of
location = element.location
size = element.size
fox.save_screenshot('screenshot.png') # saves screenshot of entire page
fox.quit()

im = Image.open('screenshot.png') # uses PIL library to open image in memory

left = location['x']
top = location['y']
right = location['x'] + size['width']
bottom = location['y'] + size['height']


im = im.crop((left, top, right, bottom)) # defines crop points
im.save('screenshot.png') # saves new cropped image