def METHOD_NAME(group_id: int, property_name: str) -> ResponseValue:
    property_group = session.session.get(PropertyGroup, group_id)
    if property_group is None:
        flash(f"Eigenschaftengruppe mit ID {group_id} existiert nicht!", 'error')
        abort(404)
    grant_property(property_group, property_name)
    session.session.commit()
    message = 'Eigenschaft {0} der Gruppe {1} gewährt.'
    flash(message.format(property_name, property_group.name), 'success')
    return redirect(url_for('.property_groups'))