Only support for single GPU?

I use the argument with --gpu 0,1,3,4, but it seems that the code only use one gpu. Is it support for multiple gpus?

Thanks.

Start by locating the Python entry point that parses the --gpu argument and tracing how the listed GPU IDs are used. Determine whether the baseline systems support multiple GPUs and define the expected behavior for --gpu 0,1,3,4. Done should include either documented single-GPU behavior or validated multi-GPU support.

Written by the indexing model from the issue text.