code: public static function findMultipleByUuidsAndExtensions($arrUuids, $arrExtensions, array $arrOptions=array())
  	{
  		if (empty($arrUuids) || empty($arrExtensions) || !\is_array($arrUuids) || !\is_array($arrExtensions))
  		{
  			return null;
  		}
  
  		foreach ($arrExtensions as $k=>$v)
  		{
  			if (!preg_match('/^[a-z0-9]{2,5}$/i', $v))
  			{
  				unset($arrExtensions[$k]);
  			}
  		}
  
  		$t = static::$strTable;
  
  		foreach ($arrUuids as $k=>$v)
  		{
  			// Convert UUIDs to binary
  			if (Validator::isStringUuid($v))
  			{
  				$v = StringUtil::uuidToBin($v);
  			}
  
  			$arrUuids[$k] = "UNHEX('" . bin2hex($v) . "')";
  		}
  
  		if (!isset($arrOptions['order']))
  		{
  			$arrOptions['order'] = "$t.uuid!=" . implode(", $t.uuid!=", $arrUuids);
  		}
  
  		return static::findBy(array("$t.uuid IN(" . implode(",", $arrUuids) . ") AND $t.extension IN('" . implode("','", $arrExtensions) . "')"), null, $arrOptions);
  	}
docs: Find multiple files by UUID and a list of extensions
  
  @param array $arrUuids      An array of file UUIDs
  @param array $arrExtensions An array of file extensions
  @param array $arrOptions    An optional options array
  
  @return Collection|FilesModel[]|FilesModel|null A collection of models or null of there are no matching files