Python multithread download images from site

main.py

#!/usr/bin/env python
# coding: utf-8

import requests as re
from bs4 import BeautifulSoup
import os
import time
from multiprocessing import cpu_count
from multiprocessing.pool import ThreadPool
import sys

# usage
# py main.py relative_path_destination_folder url

folder = sys.argv[1]
link = sys.argv[2]

response = re.get(link)

if not os.path.isdir(folder):
    os.mkdir(folder)

pics = []

def image_criteria(href):
    # add additional criteria here
    return True

soup = BeautifulSoup(response.text, "html.parser")
for link in soup.find_all("a"):
    href = link.get("href")
    # criteria for proper image links
    if href.endswith(".jpg") and image_criteria(href):
        pics.append(href)

# multithreaded download
def download(urls):
    destinations = [folder+"/"+str(j)+".jpg" for i,j in zip(urls, range(1,len(urls)+1))]
    download_parallel(zip(urls,destinations))

def download_url(args):
    t0 = time.time()
    url, fn = args[0], args[1]
    try:
        r = re.get(url)
        with open(fn, 'wb') as f:
            f.write(r.content)
        return(url, time.time() - t0)
    except Exception as e:
        print('Exception in download_url():', e)

def download_parallel(args):
    cpus = cpu_count()
    results = ThreadPool(cpus - 1).imap_unordered(download_url, args)
    for result in results:
        print('url:', result[0], 'time (s):', result[1])

if __name__ == "__main__":        
    download(pics)