강의잘듣고공부중입니다~^^작성중에 url 에 특정이미지를 크롤링하는걸 배웠는데도 에러가떠서 한수부탁드려요ㅜ

"""
dumpimages.py
    Downloads all the images on the supplied URL, and saves them to the
    specified output file ("/test/" by default)

Usage:
    python dumpimages.py https://www.1688.com// [output]
"""
from bs4 import BeautifulSoup as bs
from urllib.request import (
    urlopen, urlparse, urlunparse, urlretrieve)
import os
import sys

def main(url, out_folder="/test/"):
    """Downloads all the images at 'url' to /test/"""
    soup = bs(urlopen(url))
    parsed = list(urlparse(url))

    for image in soup.findAll("img"):
        print("Image: %(src)s" % image)
        filename = image["src"].split("/")[-1]
        parsed[2] = image["src"]
        outpath = os.path.join(out_folder, filename)
        if image["src"].lower().startswith("http"):
            urlretrieve(image["src"], outpath)
        else:
            urlretrieve(urlunparse(parsed), outpath)

def _usage():
    print("usage: python dumpimages.py http://example.com [outpath]")

if __name__ == "__main__":
    url = sys.argv[-1]
    out_folder = "/test/"
    if not url.lower().startswith("http"):
        out_folder = sys.argv[-1]
        url = sys.argv[-2]
        if not url.lower().startswith("http"):
            _usage()
            sys.exit(-1)
    main(url, out_folder)

root@goorm:/workspace/firstContainer# cd "/workspace/firstContainer";

root@goorm:/workspace/firstContainer# python3 /workspace/firstContainer/index.py

Traceback (most recent call last):

File "/workspace/firstContainer/index.py", line 38, in <module>

url = sys.argv[-2]

IndexError: list index out of range

구름ide로작성했는데 이렇게 오류가 떠요ㅠㅠ
전체이미지가 아닌 배웠던 class 특정영역의 이미지들만 일괄저장하고싶어서요;;ㅠ