Batch create resources in Revo

<?php
  //Snippet [[createResources]] by Uncle68
  $createInFolder = 0; //Set to 0 to create main folders in root, or set an existing folders id
  $parents = 4; // Number of parents to create or 0 to just create children
  $children = 25; // Number of children to create
  $template = 0; // Chose template for new docs
  $published = 1; // Published or not
 
  $output ='';  

  
  if ($parents)  {
  $x=1;$p=0;
  $output .= '<p><strong>Creating ' . $parents . ' parents/folders.</strong></p><p>'; 
    while ($p < $parents) {
      $foldertitle = 'Folder ' . $x;
      $content = 'Content ' . $x;
      
      $par = $modx->newObject('modResource');
      $par->set('pagetitle', $foldertitle);
      $par->set('content', $content);
      $par->set('published', $published); 
      $par->set('isfolder', 1); 
      $par->set('template', 2);
      if ($modx->getObject('modResource',$createInFolder)) { 
       $par->set('parent', $createInFolder);
      }
      $par->save();
      $newParents[] = $par->get('id');
      $output .= 'Created parent/folder: ' . $par->get('pagetitle') . '<br />' ;
      $p++;
      $x++;
    }
  $output .= '</p>';
  } 

  
  $x=1;$c=0;
  $output .= '<p><strong>Creating ' . $children. ' children.</strong></p><p>'; ;
while ($c < $children) {
  $childtitle = 'Child ' . $x;
  $content = 'Content ' . $x;
  
  $child = $modx->newObject('modResource');
  $child->set('pagetitle', $childtitle);
  $child->set('content', $content);
  $child->set('published', $published); 
  if (!$newParents) { $prn = $createInFolder;
  } else {
    shuffle($newParents);
    $prn = $newParents[0];
  }
  $child->set('parent', $prn); 
  $child->set('template', 2);  
  $child->save();
  $newChildren[] = $child->get('id'); //Use if you want to create children to children
  $output .= 'Created child: ' . $child->get('pagetitle') . ' with parent ' . $prn . '<br />' ;
  $c++;
  $x++;
}
  $output .= '</p>';
  
  return $output;