指数月度权重(沪深300)

获取沪深300指数月度权重，仅提供月末最后一个交易日的收盘权重信息，包括指数代码、成分股代码、权重生效日、成分权重等。通过[beginDate,endDate]组成闭区间，获取日期范围内的月末权重。

Retrieve the monthly weight data of the CSI 300 Index. Only the closing weight information on the last trading day of each month is provided, including the index code, constituent stock code, weight effective date, constituent weight and other relevant fields. You can retrieve the month-end weights within the closed interval [beginDate, endDate].