import requests
from bs4 import BeautifulSoup as bs
podcast_url='https://sponsr.ru/lulzovna/'

r=requests.get(podcast_url)
soup = bs(r.text, "html.parser")

posts = soup.find_all(class_="post-podcast-box")

for post in posts:
    text=str(post)
    end=text.find('mp3')+3
    beg=text.find('data-url=')+10
    print(text[beg:end])
    print('===')