create sharepoint group upon feature activation

CreateSharePointGroup

const string groupName = "CandidateSigned";

        // Creates group
        public static void CreateCandidateSignedPermissionGroup(SPWeb web, string groupName, string groupDescription)
        {
            SPUserCollection users = web.AllUsers;
            SPUser owner = web.SiteAdministrators[0];
            SPMember member = web.SiteAdministrators[0];
            SPGroupCollection groups = web.Groups;
            groups.Add(groupName, member, owner, groupDescription);
            SPGroup newSPGroup = groups[groupName];
            SPRoleDefinition role = web.RoleDefinitions.GetByType(SPRoleType.Administrator);
            SPRoleAssignment roleAssignment = new SPRoleAssignment(newSPGroup);
            roleAssignment.RoleDefinitionBindings.Add(role);
            web.RoleAssignments.Add(roleAssignment);
            web.Update();
        }

        // Deletes group
        public static void DeleteCandidateSignedPermissionGroup(SPWeb web, string groupName)
        {
            SPGroupCollection groups = web.SiteGroups;
            groups.Remove(groupName);
            web.Update();
        }


        // Uncomment the method below to handle the event raised after a feature has been activated.

        public override void FeatureActivated(SPFeatureReceiverProperties properties)
        {
            string groupDescription = "Games Lab verified users";
            try
            {
                using (SPWeb web = properties.Feature.Parent as SPWeb)
                {
                    SPRoleDefinition permissionLevel = web.RoleDefinitions.GetByType(SPRoleType.Contributor);
                    CreateCandidateSignedPermissionGroup(web, groupName, groupDescription);
                }
            }
            catch (Exception ex)
            {
                //ex.Message;
            }
        }


        // Uncomment the method below to handle the event raised before a feature is deactivated.

        public override void FeatureDeactivating(SPFeatureReceiverProperties properties)
        {
            try
            {
                using (SPWeb web = properties.Feature.Parent as SPWeb)
                {
                    DeleteCandidateSignedPermissionGroup(web, groupName);
                }
            }
            catch (Exception ex)
            {

            }
        }