Project Title: HomeWork

Renamed controllers, views and models
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In that case po, I think you may do this instead
```php
self::$is_username_exists = ($row['username'] === $this->username) ? true : false;
self::$is_email_exists = ($row['email'] === $this->email) ? true : false;
// or change from static to public variable
$this->is_username_exists = ($row['username'] === $this->username) ? true : false;
$this->is_email_exists = ($row['email'] === $this->email) ? true : false;
```