How to Hide Daily Prayer Time Admin Menus

function plt_hide_daily_prayer_time_for_mosques_menus() {
	//Hide "Prayer time".
	remove_menu_page('dpt');
	//Hide "Prayer time → Settings".
	remove_submenu_page('dpt', 'dpt');
	//Hide "Prayer time → API Doc".
	remove_submenu_page('dpt', 'dpt-api-doc');
	//Hide "Prayer time → Helps and Tips".
	remove_submenu_page('dpt', 'helps-and-tips');
	//Hide "Prayer time → Support Forum".
	remove_submenu_page('dpt', 'dpt-wp-support-forum');
}

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

Where do I put this code?