code: def check_if_alive(self):
          
  
          try:
              from urllib2 import urlopen, URLError, HTTPError
          except ImportError:
              from urllib.request import urlopen, URLError, HTTPError
  
          if len(self.instance.STATUS_LINK):
              check_url = self.instance.STATUS_LINK % ({'content_uid': self.get_content_uid()})
          else:
              # fallback
              check_url = self.instance.url
  
          try:
              response = urlopen(check_url)
          except (HTTPError, URLError):
              return False
          except ValueError:
              raise URLError('Invalid URL: %s'.format(check_url))
          else:
              return True if response.code == 200 else False
docs: Check if the content is available on the host server. Returns `True` if available, else `False`.
          This method is `lazy`-evaluated or only executes when called.
          :rtype: bool