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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def delete_attribute_group(group_id, **kwargs):
 """ Delete an attribute group. """

    user_id = kwargs['user_id']

    try:

        group_i = db.DBSession.query(AttrGroup).filter(AttrGroup.id==group_id).one()

        group_i.project.check_write_permission(user_id)

        db.DBSession.delete(group_i)
        db.DBSession.flush()

        log.info("Group %s in project %s deleted", group_i.id, group_i.project_id)
    except NoResultFound:

        raise HydraError('No Attribute Group %s was found', group_id)


    return 'OK'