How to Hide RevivePress Admin Menus

function plt_hide_wp_auto_republish_menus() {
	//Hide "RevivePress".
	remove_menu_page('revivepress');
	//Hide "RevivePress → Dashboard".
	remove_submenu_page('revivepress', 'revivepress');
	//Hide "RevivePress → Scheduled Tasks".
	remove_submenu_page('revivepress', 'revivepress-scheduled-tasks');
	//Hide "RevivePress → Contact Us".
	remove_submenu_page('revivepress', 'revivepress-contact');
	//Hide "RevivePress → Upgrade".
	remove_submenu_page('revivepress', 'revivepress-pricing');
}

add_action('admin_menu', 'plt_hide_wp_auto_republish_menus', 1000000000);
Where do I put this code?