input: Write a function to scrape the headlines from an online news website. The function should take a URL as input, get the response from the website, parse the contents using BeautifulSoup, and print the text of all headlines found in the parsed page. Return None.
  assert scrape_headlines("https://www.news.com/")==None
  assert scrape_headlines("https://www.anothernews.com/")==None
output: def scrape_headlines(url):
      import requests
      from bs4 import BeautifulSoup
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      headlines = soup.find_all('h1') + soup.find_all('h2') + soup.find_all('h3')
      for headline in headlines:
          print(headline.text)
      return None