func (sys *IAMSys) SetTempUser(ctx context.Context, accessKey string, cred auth.Credentials, policyName string) (time.Time, error) {
	if !sys.Initialized() {
		return time.Time{}, errServerNotInitialized
	}

	if newGlobalAuthZPluginFn() != nil {
		// If OPA is set, we do not need to set a policy mapping.
		policyName = ""
	}

	updatedAt, err := sys.store.SetTempUser(ctx, accessKey, cred, policyName)