>       
      >    class Users extends Model{
      >    public $id;
      >      public $name;
      >      public $insment;
      >     ...
      > 
      >  public static function changeInstallment($ins,$userid){
      > 
      >         $query = new Query("UPDATE Users SET insment = ".$ins."  WHERE id = ".$userid);
      > 
      >        $result = $query->execute();
      >
      >         return $result->success();
      >     }
      >when the error is : Trying to call method load on a non-object