input: Write a function to create a web crawler in Python that starts from a website and looks for other links in the page then scrapes the page content. If the given URL is invalid or cannot be accessed, return an appropriate error message.
  assert crawl("https://example.com/")==True
  assert crawl("https://invalidurl.com/")==False
  assert crawl("https://example.com/no_links_page")==True
  assert crawl("https://example.com/broken_link")==False
  assert crawl("")==False
output: def crawl(url):
      import requests
      from bs4 import BeautifulSoup
      try:
          response = requests.get(url)
          response.raise_for_status()
          soup = BeautifulSoup(response.text, 'html.parser')
          links = soup.find_all('a', href=True)
          if links:
              return True
          else:
              return False
      except (requests.RequestException, ValueError):
          return False