protected function bookInfoPid() {

		$post = ( new Metadata() )->getMetaPost();
		if ( empty( $post->ID ) ) {
			$new_post = [
				'post_title' => __( 'Book Info', 'pressbooks' ),
				'post_type' => 'metadata',
				'post_status' => 'publish',
			];
			$pid = wp_insert_post( add_magic_quotes( $new_post ) );
		} else {
			$pid = $post->ID;
		}

		return $pid;
	}