Pantheon\Terminus\Collections\Backups::getFinishedBackups PHP Method

    public function getFinishedBackups($element = null)
    {
        if (!is_null($element)) {
            $all_backups = $this->getBackupsByElement($element);
        } else {
            $all_backups = $this->all();
        }
        $finished_backups = array_filter($all_backups, function ($backup) {
            return $backup->backupIsFinished();
        });
        $ordered_backups = [];
        foreach ($finished_backups as $id => $backup) {
            $ordered_backups[$id] = $backup->get('start_time');
        }
        arsort($ordered_backups);
        $backups = [];
        foreach ($ordered_backups as $id => $start_time) {
            $backups[] = $finished_backups[$id];
        }
        return $backups;
    }