In ubercart,While buyer sees a product and clicks on add-to-cart button for buying that product, i want to know which action is responsible for that product being added in to the cart? 

I want to edit the sell price, so that only this question.
Already tried this hook, but it was not printing anything,

```
    mymodulename_uc_add_to_cart($nid, $qty, $data) {
    print "<pre>";print_r($data);print "</pre>";exit;

    if ($qty > 1) {
        $result[] = array(
                'success' => FALSE,
                'message' => t('Sorry, you can only add one of those at a time.'),
        );
    }
    return $result;
}

```

Which of these hooks 

**hook\_uc\_add\_to\_cart  

hook\_uc\_add\_to\_cart\_data  

hook\_uc\_cart\_checkout\_start  

hook\_uc\_cart\_display  

hook\_uc\_cart\_item\_delete  

hook\_uc\_cart\_item\_insert  

hook\_uc\_cart\_item\_presave  

hook\_uc\_cart\_item\_update  

hook\_uc\_cart\_pane  

hook\_uc\_cart\_pane\_alter  

hook\_uc\_checkout\_complete  

hook\_uc\_checkout\_pane  

hook\_uc\_checkout\_pane\_alter  

hook\_uc\_update\_cart\_item  

uc\_checkout\_pane\_callback**

is responsible for adding quantity and price to cart in the cart page.Or is there any other hook which is doing it ?

Any ideas? Thanks in advance