def safe_browsing(url):
    """Returns True if url is safe or False is it is suspect"""
params = urllib.parse.urlencode({'client': 'api', 'apikey': 'yourkey', 'appver':
    '1.5.2', 'pver': '3.0', 'url': url})
url = 'https://sb-ssl.google.com/safebrowsing/api/lookup?%s' % params
res = urlfetch.fetch(url, method=urlfetch.GET)
if res.status_code >= 400:
    raise Exception('Status: %s' % res.status_code)
Неверный запрос в Google Safe-Browsing Lookup API