def _merge_perm(self, permission_name, view_menu_name):
        """
        
        """
        permission = self.find_permission(permission_name)
        view_menu = self.find_view_menu(view_menu_name)
        pv = None
        if permission and view_menu:
            pv = self.get_session.query(self.permissionview_model).filter_by(
                permission=permission, view_menu=view_menu).first()
        if not pv and permission_name and view_menu_name:
            self.add_permission_view_menu(permission_name, view_menu_name)