Source

File: wp-admin/includes/class-wp-list-table.php

public function ajax_response() {
		$this->prepare_items();

		ob_start();
		if ( ! empty( $_REQUEST['no_placeholder'] ) ) {
			$this->display_rows();
		} else {
			$this->display_rows_or_placeholder();
		}

		$rows = ob_get_clean();

		$response = array( 'rows' => $rows );

		if ( isset( $this->_pagination_args['total_items'] ) ) {
			$response['total_items_i18n'] = sprintf(
				/* translators: Number of items. */
				_n( '%s item', '%s items', $this->_pagination_args['total_items'] ),
				number_format_i18n( $this->_pagination_args['total_items'] )
			);
		}
		if ( isset( $this->_pagination_args['total_pages'] ) ) {
			$response['total_pages']      = $this->_pagination_args['total_pages'];
			$response['total_pages_i18n'] = number_format_i18n( $this->_pagination_args['total_pages'] );
		}

		die( wp_json_encode( $response ) );
	}