Extending core class IncomingRequest

Hello folks.

Someone has an idea of how making this work?

app/Libraries/IncomingRequest.php

PHP Code:

<?php
namespace App\Libraries;
use CodeIgniter\HTTP\IncomingRequest;

class IncomingRequest extends IncomingRequest {

    public function __construct(...Same args as in original...) {
       exit('I DONT SEE THIS');
       parent::__construct(...Same args as in original..);
    }
} 


I'm actually trying to make some changes to method getPost(), but this file doesn't seem to be working at all.