How to Hide WP Speed Optimization By Add Expires Headers & Optimized Minify Plugin Admin Menus

function plt_hide_add_expires_headers_menus() {
	//Hide "Add Expires Headers".
	remove_menu_page('aeh_pro_plugin_options');
	//Hide "Add Expires Headers → Add Expires Headers".
	remove_submenu_page('aeh_pro_plugin_options', 'aeh_pro_plugin_options');
	//Hide "Add Expires Headers → Affiliation".
	remove_submenu_page('aeh_pro_plugin_options', 'aeh_pro_plugin_options-affiliation');
	//Hide "Add Expires Headers → Contact Us".
	remove_submenu_page('aeh_pro_plugin_options', 'aeh_pro_plugin_options-contact');
	//Hide "Add Expires Headers → Upgrade".
	remove_submenu_page('aeh_pro_plugin_options', 'aeh_pro_plugin_options-pricing');
}

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

Where do I put this code?