fixed the issue of DPO trainer that using one node and mutiple GPUs and set the device_map='auto' (#29695)
* fixed the issue of DPO trainer that using one node and mutiple GPUs
* before update, add the assert
* run the ruff formatter
* Update src/transformers/trainer.py
Thank you.
Co-authored-by: Younes Belkada <49240599+younesbelkada@users.noreply.github.com>
* remember to do make style and make quality before commit
* Update src/transformers/trainer.py
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>
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Co-authored-by: Younes Belkada <49240599+younesbelkada@users.noreply.github.com>
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>