'Returns the instance id a floating IP\'s fixed IP is allocated to.'

def get_instance_id_by_floating_address(self, context, address):

    LOG.debug('Get    instance    for    floating    address    %s', address)
    fixed_ip = objects.FixedIP.get_by_floating_address(context, address)
    if (fixed_ip is None):
        return None
    else:
        return fixed_ip.instance_uuid
