code: def set_cookie_prefix(self, cookie_prefix=None):
          
          if (cookie_prefix is None):
              self.cookie_prefix = "%06d_" % int(random.random() * 1000000)
          else:
              self.cookie_prefix = cookie_prefix
docs: Set a random cookie prefix unless one is specified.
  
          In order to run multiple demonstration auth services on the
          same server we need to have different cookie names for each
          auth domain. Unless cookie_prefix is set, generate a random
          one.