A股数据 API 官方 Python SDK —— 行情/K线/分时/财务/资金/龙虎榜/板块/因子选股/量化回测(40 端点,免费端点无需注册)|Official Python SDK for the A-Share Data API — quotes, K-lines, financials, money flow, dragon-tiger lists, sectors, factor screening and quant backtests (40 endpoints, free endpoints need no signup)