/// <summary>
        /// Processes the system role command.
        /// </summary>
        /// <param name="systemRole">The system role.</param>
        /// <param name="request">The request.</param>
        protected override void ProcessSystemRoleCommand(SystemRole systemRole, RevokeSystemPermissionRequest request)
        {
            var session = SessionProvider.GetSession();

            foreach (var systemPermissionKeyToBeGranted in request.SystemPermissionKeysToBeRevoked)
            {
                var systemPermissionToBeRevoked = session.Get <SystemPermission> (systemPermissionKeyToBeGranted);

                systemRole.RevokeSystemPermission(systemPermissionToBeRevoked);
            }
        }