When I was running LSO_eval.py, I got an error for the assert statement on line 490 which checks if a CUDA GPU is available.
On line 447, I replaced os.environ["CUDA_VISIBLE_DEVICES"]="1" with os.environ["CUDA_VISIBLE_DEVICES"]="0" and it worked.
FYI, I was running this on a Linux machine with only a single T4 GPU (maybe the code works for a different configuration).