rector/config/set/level/up-to-php55.php

<?php

declare (strict_types=1);
namespace RectorPrefix20220601;

use Rector\Config\RectorConfig;
use Rector\Core\ValueObject\PhpVersion;
use Rector\Set\ValueObject\LevelSetList;
use Rector\Set\ValueObject\SetList;
return static function (\Rector\Config\RectorConfig $rectorConfig) : void {
    $rectorConfig->sets([\Rector\Set\ValueObject\SetList::PHP_55, \Rector\Set\ValueObject\LevelSetList::UP_TO_PHP_54]);
    // parameter must be defined after import, to override imported param version
    $rectorConfig->phpVersion(\Rector\Core\ValueObject\PhpVersion::PHP_55);
};