How to Hide the ""Seeya" settings" Admin Menu

function plt_hide_page_blocker_seeya_menus() {
	//Hide the "Plugins → "Seeya" settings" menu.
	remove_submenu_page('plugins.php', 'seeya-settings');
}

add_action('admin_menu', 'plt_hide_page_blocker_seeya_menus', 11);

Where do I put this code?