public function set_sku( $sku ) {
		$sku = (string) $sku;
		if ( $this->get_object_read() && ! empty( $sku ) && ! wc_product_has_unique_sku( $this->get_id(), $sku ) ) {
			$sku_found = wc_get_product_id_by_sku( $sku );

			$this->error( 'product_invalid_sku', __( 'Invalid or duplicated SKU.', 'woocommerce' ), 400, array( 'resource_id' => $sku_found ) );
		}
		$this->set_prop( 'sku', $sku );
	}