Generate SRV record data
    :param target:
    :param port:
    :param prio:
    :param weight:
    :return:

def srv_data(target, port, prio=10, weight=10):
    '''
    Generate SRV record data
    :param target:
    :param port:
    :param prio:
    :param weight:
    :return:
    '''
    return _rec2data(prio, weight, port, target)