'Remove data structures for a given subnet.
IPAM-related data has no foreign key relationships to neutron subnet,
so removing ipam subnet manually'

def remove_subnet(self, subnet_id):

    count = ipam_db_api.IpamSubnetManager.delete(self._context, subnet_id)
    if (count < 1):
        LOG.error(_LE('IPAM    subnet    referenced    to    Neutron    subnet    %s    does    not    exist'), subnet_id)
        raise n_exc.SubnetNotFound(subnet_id=subnet_id)
