Restructure train/: nest shards into chunk subdirs (batch 97/98)

Restructure train/: nest shards into chunk subdirs (batch 54/98)

Restructure train/: nest shards into chunk subdirs (batch 53/98)

Restructure train/: nest shards into chunk subdirs (batch 52/98)

Restructure train/: nest shards into chunk subdirs (batch 51/98)

Restructure train/: nest shards into chunk subdirs (batch 50/98)

Restructure train/: nest shards into chunk subdirs (batch 49/98)

Restructure train/: nest shards into chunk subdirs (batch 48/98)