python - Python：解决 IsADirectoryError：尝试从 csv 文件中列出的链接下载 pdf 时

Question

我已经设置了一个 API，它在 csv 文件的列中返回 pdf 链接。现在我需要依次下载这些 pdf 文档。但是它返回 IsADirectoryError: [Errno 21] Is a directory: 当有空白行或 html 而不是 pdf 链接并停止时。解决方法是什么？谢谢。

我正在使用此代码。

import os
import csv
import requests

write_path = '</pathname>'  # ASSUMING THAT FOLDER EXISTS!

with open('</**.csv>', 'r') as csvfile:
    os.listdir(write_path)) if os.path.isfile(i)]
    spamreader = csv.reader(csvfile)
    for link in spamreader:
        print('-'*72)
        pdf_file = link[4].split('/')[-1]


        with open(os.path.join(write_path, pdf_file), 'wb') as pdf:
            try:
                # Try to request PDF from URL
                print('TRYING {}...'.format(link[4]))
                a = requests.get(link[4], stream=True)


                for block in a.iter_content(512):
                    if not block:

                     break
                     pdf.write(block)
                print('OK.')


            except requests.exceptions.RequestException as e:  
                print('REQUESTS ERROR:')
                print(e)