How to Hide WowOptin Admin Menus

function plt_hide_optin_menus() {
	//Hide "WowOptin".
	remove_menu_page('wowoptin');
	//Hide "WowOptin → Dashboard".
	remove_submenu_page('wowoptin', 'wowoptin-dashboard');
	//Hide "WowOptin → Optins".
	remove_submenu_page('wowoptin', 'wowoptin-optins');
	//Hide "WowOptin → Templates".
	remove_submenu_page('wowoptin', 'wowoptin-templates');
	//Hide "WowOptin → Leads".
	remove_submenu_page('wowoptin', 'wowoptin-leads');
	//Hide "WowOptin → A/B Testing".
	remove_submenu_page('wowoptin', 'wowoptin-ab-test');
	//Hide "WowOptin → Integrations".
	remove_submenu_page('wowoptin', 'wowoptin-integrations');
	//Hide "WowOptin → Settings".
	remove_submenu_page('wowoptin', 'wowoptin-settings');
	//Hide "WowOptin → Support".
	remove_submenu_page('wowoptin', 'wowoptin-support');
	//Hide "WowOptin → Builder".
	remove_submenu_page('wowoptin', 'wowoptin-builder');
	//Hide "WowOptin → Upgrade to Pro".
	remove_submenu_page('wowoptin', 'wowoptin-pro');
}

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

Where do I put this code?