Turn on two lights simultaneously

[hoainamken]

Hi,

Thank you for your library.

I have been able to turn on each light(8 leds each) sequentially. Now I have a while loop, and inside it, I need to turn on at least two lights at the same time for each iteration.
When I use multi-thread to do this, it keeps saying Could not communicate with BlinkStick <serial> - it may have been removed
B/c of that, I tried another way, that is using some sort of async functions in python, however, I got the error:
python: ../../libusb/io.c:2118: handle_events: Assertion ctx->pollfds_cnt >= internal_nfds' failed.`

Is there any ways to do this?
Thanks