$ total_paid获取价值Prestashop

I'm confused. Try a lot of function/classes and nothing.

Please help my to understand in what file and function, $total_paid gets value?

The reason is why I need it, because I want to edit e-mail template /mails/en/bankwire.html at line:

<span style="color:#333"><strong>Amount:</strong></span> {total_paid}<br />

Thanks

UPD:

It's not duplicate of this question it's nearby but not exactly what I need. I post my question before see it. In my answer I will show more details of solving my question.

For edit $total_paid variable I edit some code in classes/PaymentModule.php function validateOrder() which start at line 252 with:

foreach ($package_list as $id_address => $packageByAddress)
    foreach ($packageByAddress as $id_package => $package)
    {
        $order = new Order();
        $order->product_list = $package['product_list'];

…

And at line 321 I found this string:

$order->total_paid = $order->total_paid_tax_incl;

After line 321 I can change value for $total_paid by adding what I need to $order->total_paid

Thanks to Garry Cooper his answer gave my a right direction for solve my question