How to Hide DebugPress: Debugger in Popup Admin Menus

function plt_hide_debugpress_menus() {
	//Hide the "Tools → DebugPress Info" menu.
	remove_submenu_page('tools.php', 'debugpress-info');
	//Hide the "Settings → DebugPress" menu.
	remove_submenu_page('options-general.php', 'debugpress');
}

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

Where do I put this code?