input: Write a python function to develop a web crawler that crawls the web based on the given keyword, parses the data and stores it.
  assert len(crawl_web('python')) > 0
  assert isinstance(crawl_web('javascript'), list)
  assert all(isinstance(item, dict) for item in crawl_web('web development'))
output: import requests
  from bs4 import BeautifulSoup
  
  def crawl_web(keyword):
      search_url = f"https://www.google.com/search?q={keyword}"
      headers = {'User-Agent': 'Mozilla/5.0'}
      
      response = requests.get(search_url, headers=headers)
      soup = BeautifulSoup(response.text, 'html.parser')
      
      results = []
      for g in soup.find_all('div', class_='tF2Cxc'):
          title = g.find('h3').text if g.find('h3') else 'No title'
          link = g.find('a')['href'] if g.find('a') else 'No link'
          snippet = g.find('span', class_='aCOpRe').text if g.find('span', class_='aCOpRe') else 'No snippet'
          
          results.append({
              'title': title,
              'link': link,
              'snippet': snippet
          })
      
      return results