How to Hide Vision - Interactive Image Map Builder Admin Menus

function plt_hide_vision_menus() {
	//Hide "Vision".
	remove_menu_page('vision');
	//Hide "Vision → All Items".
	remove_submenu_page('vision', 'vision');
	//Hide "Vision → Add New".
	remove_submenu_page('vision', 'vision_item');
	//Hide "Vision → Settings".
	remove_submenu_page('vision', 'vision_settings');
	//Hide "Vision → Upgrade to Pro".
	remove_submenu_page('vision', 'vision_upgrade_to_pro');
}

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

Where do I put this code?