sample_lis.json files has mapping for just one entity

[ayushi-3536]

Hi

Thank you for your amazing work

I was trying to setup some experiment and found that for stage 2 the provided file sample_list.json has mapping for only one entity with index 66, is this expected?

Thanks

[Jazzcharles]

We have updated the code and simplify the sampling process. Please refer to docs/DATA_README.md.