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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 get_group_attributegroup_items(network_id, group_id, **kwargs):
 """ Get all the items in a specified group, within a network """

    user_id=kwargs.get('user_id')

    network_i = _get_network(network_id)

    network_i.check_read_permission(user_id)

    group_items_i = db.DBSession.query(AttrGroupItem).filter(
                                    AttrGroupItem.network_id==network_id,
                                    AttrGroupItem.group_id==group_id).all()

    return group_items_i