执行文件的时候会报'str' object has no attribute 'value'是为什么呢，有朋友知道为什么吗，单行的数据就是执行成功的
Traceback (most recent call last):
File line 37, in <module>
database_manager.save_bar_data(bars)
File "/opt/anaconda3/lib/python3.12/site-packages/vnpy_sqlite/sqlite_database.py", line 167, in save_bar_data
d["exchange"] = d["exchange"].value
^^^^^^^^^^^^^^^^^^^
AttributeError: 'str' object has no attribute 'value'
