Super secret EE code

gistfile1.aw

// /system/expressionengine/libraries/Template.php (line 3030)
// Member Group in_group('1') function, Super Secret!  Shhhhh!		
if (preg_match_all("/in_group\(([^\)]+)\)/", $str, $matches))
{
  $groups = (is_array($this->EE->session->userdata['group_id'])) ? $this->EE->session->userdata['group_id'] : array($this->EE->session->userdata['group_id']);

  for($i=0, $s=count($matches[0]); $i < $s; ++$i)
  {
    $check = explode('|', str_replace(array('"', "'"), '', $matches[1][$i]));

    $str = str_replace($matches[0][$i], (count(array_intersect($check, $groups)) > 0) ? 'TRUE' : 'FALSE', $str);
  }
}