woocommerce/plugins/woocommerce-admin/includes/class-wc-admin-reports-query.php

<?php
/**
 * Class for parameter-based Reports querying
 *
 * @package  WooCommerce Admin/Classes
 */

defined( 'ABSPATH' ) || exit;

/**
 * WC_Admin_Reports_Query
 *
 */
abstract class WC_Admin_Reports_Query extends WC_Object_Query {

	/**
	 * Get report data matching the current query vars.
	 *
	 * @return array|object of WC_Product objects
	 */
	public function get_data() {
		/* translators: %s: Method name */
		return new WP_Error( 'invalid-method', sprintf( __( "Method '%s' not implemented. Must be overridden in subclass.", 'woocommerce' ), __METHOD__ ), array( 'status' => 405 ) );
	}

}