获取TypeError：期望的字符串或类似字节的对象

Question

我的代码：

import urllib.request
for num in range(1,31):
    URL= "http://readcomicbooksonline.net/reader/mangas/Batman 2011/Batman Endgame Special Edition/njqr-"
    IMAGE = str(num)+".jpg"
    for i in range(1,(3-int(num/10))):
        IMAGE="0"+IMAGE
    print (IMAGE)
    req = urllib.request.Request(str(URL+IMAGE), headers={'User-Agent': 'Mozilla/5.0'})
    urllib.request.urlretrieve(req, str(IMAGE))

错误：

Traceback (most recent call last):
      File "E:\Books, Papers and Certificates\Comics\Batman\EndGame\downloader.py", line 9, in <module>
        urllib.request.urlretrieve(req, str(IMAGE))
      File "C:\Users\Baidyanath Kundu\AppData\Local\Programs\Python\Python36-32\lib\urllib\request.py", line 246, in urlretrieve
        url_type, path = splittype(url)
      File "C:\Users\Baidyanath Kundu\AppData\Local\Programs\Python\Python36-32\lib\urllib\parse.py", line 924, in splittype
        match = _typeprog.match(url)
    TypeError: expected string or bytes-like object

已编辑抱歉，我的错误是我发布了以前版本的代码。我已经更新了它。