code: def _check_timestamp(self, timestamp):
          
          timestamp = int(timestamp)
          now = int(time.time())
          lapsed = now - timestamp
          if lapsed > self.timestamp_threshold:
              raise Error('Expired timestamp: given %d and now %s has a '
                  'greater difference than threshold %d' % (timestamp, now, 
                      self.timestamp_threshold))
docs: Verify that timestamp is recentish.