Hi, the installation instruction tells us to "Step1: Add PHP Grid configuration code". Which file is the code meant to be added to?

Here's the code being referenced:
?php
include_once("../../config.php");

// set up DB
mysql_connect(PHPGRID_DBHOST, PHPGRID_DBUSER, PHPGRID_DBPASS);
mysql_select_db(PHPGRID_DBNAME);

// include and create object
include(PHPGRID_LIBPATH."inc/jqgrid_dist.php");

// set few params
$grid["caption"] = "Sample Grid";
$g->set_options($grid);

// set database table for CRUD operations
$g->table = "clients";

// render grid and get html/js output
$out = $g->render("list1");
?>

Thank you