input: Write a function to build a web scraper in Python that collects all the links from a given website URL. Return a list of all the links (href values) found on the webpage. If the given URL is empty, return an empty list.
  assert scrape_links("http://www.example.com/")==['http://www.iana.org/domains/example']
  assert scrape_links("http://www.example.org/")==['http://www.iana.org/domains/reserved']
  assert scrape_links("")==[]
output: def scrape_links(url):
      if not url:
          return []
      import requests
      from bs4 import BeautifulSoup
      response = requests.get(url)
      soup = BeautifulSoup(response.text, 'html.parser')
      links = [a['href'] for a in soup.find_all('a', href=True)]
      return links