How to use the saml.assertion.lifespan function in saml

$scope.samlServerSignatureEnableKeyInfoExtension = false;
    $scope.samlAssertionSignature = false;
    $scope.samlClientSignature = false;
    $scope.samlEncrypt = false;
    $scope.samlForcePostBinding = false;
    $scope.samlForceNameIdFormat = false;
    $scope.samlXmlKeyNameTranformer = $scope.xmlKeyNameTranformers[1];
    $scope.disableAuthorizationTab = !client.authorizationServicesEnabled;
    $scope.disableServiceAccountRolesTab = !client.serviceAccountsEnabled;
    $scope.disableCredentialsTab = client.publicClient;
    // KEYCLOAK-6771 Certificate Bound Token
    // https://tools.ietf.org/html/draft-ietf-oauth-mtls-08#section-3
    $scope.tlsClientCertificateBoundAccessTokens = false;

    $scope.accessTokenLifespan = TimeUnit2.asUnit(client.attributes['access.token.lifespan']);
    $scope.samlAssertionLifespan = TimeUnit2.asUnit(client.attributes['saml.assertion.lifespan']);

    if(client.origin) {
        if ($scope.access.viewRealm) {
            Components.get({realm: realm.realm, componentId: client.origin}, function (link) {
                $scope.originName = link.name;
                //$scope.originLink = "#/realms/" + realm.realm + "/user-storage/providers/" + link.providerId + "/" + link.id;
            })
        }
        else {
            // KEYCLOAK-4328
            ClientStorageOperations.simpleName.get({realm: realm.realm, componentId: client.origin}, function (link) {
                $scope.originName = link.name;
                //$scope.originLink = $location.absUrl();
            })
        }
    } else {

$scope.updateAssertionLifespan = function() {
        if ($scope.samlAssertionLifespan.time) {
            $scope.clientEdit.attributes['saml.assertion.lifespan'] = $scope.samlAssertionLifespan.toSeconds();
        } else {
            $scope.clientEdit.attributes['saml.assertion.lifespan'] = null;
        }
    }