input: Write a function to scrape an online news website and extract the headlines. The function should take the URL of the website as input, use the requests and BeautifulSoup libraries to parse the content, and then print the text of all the headlines found on the page.
  
  assert scrape_headlines("https://www.example-news.com/") == ["Example Headline 1", "Example Headline 2"]
  assert scrape_headlines("https://www.sample-news.com/") == ["Sample Headline 1", "Sample Headline 2"]
  assert scrape_headlines("https://www.test-news.com/") == ["Test Headline 1", "Test Headline 2"]
  assert scrape_headlines("https://www.mock-news.com/") == ["Mock Headline 1", "Mock Headline 2"]
  assert scrape_headlines("https://www.demo-news.com/") == []
output: def scrape_headlines(url):
      import requests
      from bs4 import BeautifulSoup
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      headlines = [headline.text for headline in soup.find_all('h1')]
      return headlines