def METHOD_NAME(cls) -> Set:
    """
    Returns only fields that are stored in the own database table, exclude all
    related fields.
    :return: set of model fields with relation fields excluded
    :rtype: Set
    """
    related_names = cls.extract_related_names()
    self_fields = {
        name for name in cls.Meta.model_fields.keys() if name not in related_names
    }
    return self_fields