public function require_classes() {
		// if Tribe__PUE__Checker exists, PUE has already been bootstrapped by another plugin
		if ( class_exists( 'Tribe__PUE__Checker' ) ) {
			return;
		}

		require_once $this->plugin_path . '/src/functions/template-tags/general.php';
		require_once $this->plugin_path . '/src/Tribe/Assets.php';
		require_once $this->plugin_path . '/src/Tribe/Autoloader.php';
		require_once $this->plugin_path . '/src/Tribe/PUE/Checker.php';
		require_once $this->plugin_path . '/src/Tribe/PUE/Notices.php';
		require_once $this->plugin_path . '/src/Tribe/PUE/Package_Handler.php';
		require_once $this->plugin_path . '/src/Tribe/PUE/Plugin_Info.php';
		require_once $this->plugin_path . '/src/Tribe/PUE/Utility.php';
		require_once $this->plugin_path . '/src/Tribe/Admin/Helpers.php';
		require_once $this->plugin_path . '/src/Tribe/Admin/Notices.php';
		require_once $this->plugin_path . '/src/Tribe/Settings_Manager.php';
	}