code: public function createGroup($files)
      {
          $data = array(
              'pub_key' => $this->api->getPublicKey(),
          );
          /**
           * @var File $file
           */
          foreach ($files as $i => $file) {
              $data["files[$i]"] = $file->getUrl();
          }
  
  
          $ch = $this->__initRequest('group');
          $this->__setRequestType($ch);
          $this->__setData($ch, $data);
          $this->__setHeaders($ch);
  
          $resp = $this->__runRequest($ch);
          $group = $this->api->getGroup($resp->id);
          return $group;
      }
docs: Create group from array of File objects
  
  @param array $files
  @return Group
  @throws \Exception