input: Write a python function to scrape a website and return paragraphs containing a search term.
  assert scrape_website('https://www.example.com/', 'example') == '<p>Example Domain</p>'
  assert scrape_website('https://www.example.com/', 'domain') == '<p>Example Domain</p>'
  assert scrape_website('https://www.example.com/', 'notfound') == ''
output: def scrape_website(url, search_term):
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      paragraphs = soup.find_all('p')
  
      result = ''
      for p in paragraphs:
          if search_term.lower() in p.get_text().lower():
              result += str(p)
  
      return result