/**
 * Implements hook_menu_get_item_alter().
 */
function {{ machine_name }}_menu_get_item_alter(&$router_item, $path, $original_map) {
  // When retrieving the router item for the current path...
  if ($path == $_GET['q']) {
    // ...call a function that prepares something for this request.
    mymodule_prepare_something();
  }
}