应该是时间格式的问题，而且修改以后要重新启动vnpy，谢谢各位

with open(r'D:\历史数据\SHSE_000001.csv', 'r') as f:
reader = csv.DictReader(f)
bars = []
start = None
count = 0
for item in reader:
item['bob'] = item['bob'].replace('+08:00', "")
dt = datetime.strptime(item['bob'], '%Y-%m-%d %H:%M:%S')
bar = BarData(
symbol='000001',
datetime=dt,
exchange=Exchange.SHFE,
interval=Interval.DAILY,
volume=item['volume'],
open_price=item['open'],
high_price=item['high'],
low_price=item['low'],
close_price=item['close'],
gateway_name='db'
)
bars.append(bar)
count += 1
if not start:
start = bar.datetime
end = bar.datetime
database_manager.save_bar_data(bars)

不知道为什么会出现这种情况，对比代码想了很久了没想明白，求指点