docs: def SecurityCheck(self, func, request, *args, **kwargs):
      """Wrapping function."""
      if self.IAP_HEADER not in request.headers:
        return werkzeug_wrappers.Response("Unauthorized", status=401)
  
      jwt = request.headers.get(self.IAP_HEADER)
      try:
        request.user, _ = validate_iap.ValidateIapJwtFromComputeEngine(
            jwt, self.cloud_project_id, self.backend_service_id)
        return func(request, *args, **kwargs)
  
      except validate_iap.IAPValidationFailedError as e:
        # Return failure if IAP is not decoded correctly.
        logging.error("IAPWebAuthManager failed with: %s", e)
        return werkzeug_wrappers.Response("Unauthorized", status=401)