download.py

import os
import re
import sys
import time
from urllib.request import urlretrieve

channel = sys.argv[1]

with open(f'{channel}.txt', 'rt') as f:
  lines = f.readlines()

if not os.path.exists(channel):
  os.makedirs(channel)

for url in lines:
  name = re.findall(r'(?<=vi/).*(?=/hqdefault)', url)[0]
  path = os.path.join(channel, f'{name}.jpg')

  if os.path.exists(path):
    print(f'{path} already exists')
    continue

  print(f'download {path}')
  urlretrieve(url, path)
  time.sleep(1)