code: func (db ErroringDB) IsInWhitelist(c context.Context, ip net.IP, whitelist string) (bool, error) {
  	logging.Errorf(c, "%s", db.Error)
  	return false, db.Error
  }
docs: // IsInWhitelist returns true if IP address belongs to given named IP whitelist.
  //
  // IP whitelist is a set of IP subnets. Unknown IP whitelists are considered
  // empty. May return errors if underlying datastore has issues.