user/user_vm.go
func IsAdmin(c context.Context) bool {
	h := internal.IncomingHeaders(c)
	return h.Get("X-AppEngine-User-Is-Admin") == "1"
}
func IsAdmin(c context.Context) bool {
	h := internal.IncomingHeaders(c)
	return h.Get("X-AppEngine-User-Is-Admin") == "1"
}
// IsAdmin returns true if the current user is signed in and
// is currently registered as an administrator of the application.