def get_records(value):
Log("get records day:",value)
records = exchange.GetRecords(PERIOD_D1)
res = 0
for i in range(-(value + 1),-1):
res = res + records[i]["Close"]
Log("time:", records[i]["Time"], "value:",records[i]["Close"])
return res/value

通过此函数计算均线
回测中，实盘的k线周期无法设置成天，所以records的长度往往只有5，6天，无法获取30日均线，改怎么解决？