Exception output when creating PikaStdDevice.Time()

 Exception prints time.struct_time when creating PikaStdDevice.Time().

```
>>> t = PikaStdDevice.Time()
time.structure_time(tm_year=1970, tm_mon=1,tm_mday=1, tm_hour=8, tm_min=0, tm_sec=0, tm_wday=4,tm_day=1, tm_isdst=-)
>>>
``` 

@OnceDay11  Is it considered to check this issue and provide a fix? Thanks.
