How to Hide Smart Auto Featured Image Admin Menus

function plt_hide_smart_auto_featured_image_menus() {
	//Hide "Smart Auto Featured Image".
	remove_menu_page('smart-auto-featured-image_template_editor');
	//Hide "Smart Auto Featured Image → Template manager".
	remove_submenu_page('smart-auto-featured-image_template_editor', 'smart-auto-featured-image_template_editor');
	//Hide "Smart Auto Featured Image → Settings".
	remove_submenu_page('smart-auto-featured-image_template_editor', 'smart-auto-featured-image_settings');
	//Hide "Smart Auto Featured Image → Upgrade".
	remove_submenu_page('smart-auto-featured-image_template_editor', 'smart-auto-featured-image_template_editor-pricing');
}

add_action('admin_menu', 'plt_hide_smart_auto_featured_image_menus', 1000000000);

Where do I put this code?