transformers

bdaddb6f - Document new default shard size + dropped unsafe serialization (#42904)

Document new default shard size + dropped unsafe serialization (#42904) * Document new default shard size + dropped unsafe serialization * a * Update MIGRATION_GUIDE_V5.md Co-authored-by: Cyril Vallez <cyril.vallez@huggingface.co> --------- Co-authored-by: Cyril Vallez <cyril.vallez@huggingface.co>