Exchange.IO 使用手册里面的例子报错

var symbols = [“BTC_USDT”, “LTC_USDT”, “EOS_USDT”, “ETH_USDT”, “BCC_USDT”]; var buyValue = 1000; function main(){ for(var i=0;i<symbols.length;i++){ exchange.IO("currency", symbols[i]); var ticker = exchange.GetTicker(); var amount = _N(buyValue/ticker.Sell, 3); exchange.Buy(ticker.Sell, amount); Sleep(1000); } }

我用bitfinex BTC_USDT交易平台做模拟回测，就看到这个error。上面代码是Exchange的API说明书里的：https://fmz-docs.readthedocs.io/en/latest/code_Instruction/Extent API.html#io 怎么破？ main:5:18 - TypeError: Cannot convert “BTC_USDT” to int