1. Go to this page and download the library: Download prhost/cep-gratis library. Choose the download type require.
2. Extract the ZIP file and open the index.php.
3. Add this code to the index.php.
<?php
require_once('vendor/autoload.php');
/* Start to develop here. Best regards https://php-download.com/ */
prhost / cep-gratis example snippets
use Prhost\CepGratis\CepGratis;
$address = CepGratis::search('31030080');