用于生成特定的券商对象
    :param broker:券商名支持 ['yh_client', '银河客户端'] ['ht_client', '华泰客户端']
    :param debug: 控制 debug 日志的显示, 默认为 True
    :param initial_assets: [雪球参数] 控制雪球初始资金，默认为一百万
    :return the class of trader

    Usage::

        >>> import easytrader
        >>> user = easytrader.use('xq')
        >>> user.prepare('xq.json')

def use(broker, debug=True, **kwargs):
    """用于生成特定的券商对象
    :param broker:券商名支持 ['yh_client', '银河客户端'] ['ht_client', '华泰客户端']
    :param debug: 控制 debug 日志的显示, 默认为 True
    :param initial_assets: [雪球参数] 控制雪球初始资金，默认为一百万
    :return the class of trader

    Usage::

        >>> import easytrader
        >>> user = easytrader.use('xq')
        >>> user.prepare('xq.json')
    """
    if not debug:
        log.setLevel(logging.INFO)
    if broker.lower() in ["xq", "雪球"]:
        return XueQiuTrader(**kwargs)
    if broker.lower() in ["yh_client", "银河客户端"]:
        from .yh_clienttrader import YHClientTrader

        return YHClientTrader()
    if broker.lower() in ["ht_client", "华泰客户端"]:
        from .ht_clienttrader import HTClientTrader

        return HTClientTrader()
    if broker.lower() in ["gj_client", "国金客户端"]:
        from .gj_clienttrader import GJClientTrader

        return GJClientTrader()
    if broker.lower() in ["ths", "同花顺客户端"]:
        from .clienttrader import ClientTrader

        return ClientTrader()

    raise NotImplementedError