old_contents: import requests
  from bs4 import BeautifulSoup
  
  host = 'https://www.youtube.com'
  url = 'https://www.youtube.com/playlist?list=PLU6BYY1Lu_feVbuZEscpd6xT32zCrVrev'
  r = requests.get(url)
  
  soup = BeautifulSoup(r.content)
  
  links = soup.tbody.find_all('a', 'pl-video-title-link')
  
  url_list = [host + link['href'].split('&')[0] for link in links]
  
  with open('urls.txt', 'wb') as f:
      f.writelines(url_list)
  
new_contents: import requests
  from bs4 import BeautifulSoup
  
  host = 'https://www.youtube.com'
  url = 'https://www.youtube.com/playlist?list=PLU6BYY1Lu_feVbuZEscpd6xT32zCrVrev'
  r = requests.get(url)
  
  soup = BeautifulSoup(r.content)
  
  links = soup.tbody.find_all('a', 'pl-video-title-link')
  
  url_list = [host + link['href'].split('&')[0] for link in links]
  
  with open('urls.txt', 'rw+') as f:
      f.writelines(url_list)
  
subject: write to file for easier development