How to set Validation Labels on Model

PHP Code:

class Users extends \CodeIgniter\Model
{        
    protected $validationRules = [
        'username' => [
            'label' => 'Usuario', 
            'rules' => 'required|alpha_numeric_space|min_length[3]|max_length[16]|is_unique[users.username,id,{id}]',
        ],
    ];
} 


Thank you! It solved my question