@classmethod
def get_list(cls, criteria={'id__isnull': False}, exclude={'id__isnull': 
    True}, order_by=['id']):
    """
        Get list of objects optionaly filtered by criteria
        :param user_id: id of owner
        :param criteria: django dictionary with criteria (e.g. name="abcd")
        :param order_by: python list with field names, which will sort objects. By default this is id
        :return: Queryset or empty python's list
        """
    try:
        return cls.objects.filter(**criteria).exclude(**exclude).order_by(*
            order_by)
    except:
        return []
