Version 2.9 of transformers introduces a new Trainer class for PyTorch, and its equivalent TFTrainer for TF 2. Running the examples requires PyTorch 1.3.1+ or TensorFlow 2.0+.

Here is the list of all our examples:

• grouped by task (all official examples work for multiple models)
• with information on whether they are built on top of Trainer/TFTrainer (if not, they still work, they might just lack some features),
• whether they also include examples for pytorch-lightning, which is a great fully-featured, general-purpose training library for PyTorch,
• links to Colab notebooks to walk through the scripts and run them easily,
• links to Cloud deployments to be able to deploy large-scale trainings in the Cloud with little to no setup.

This is still a work-in-progress – in particular documentation is still sparse – so please contribute improvements/pull requests.

Task	Example datasets	Trainer support	TFTrainer support	pytorch-lightning	Colab
language-modeling	Raw text	✅	-	-
text-classification	GLUE, XNLI	✅	✅	✅
token-classification	CoNLL NER	✅	✅	✅	-
multiple-choice	SWAG, RACE, ARC	✅	✅	-
question-answering	SQuAD	-	✅	-	-
text-generation	-	n/a	n/a	n/a
distillation	All	-	-	-	-
summarization	CNN/Daily Mail	-	-	-	-
translation	WMT	-	-	-	-
bertology	-	-	-	-	-
adversarial	HANS	✅	-	-	-

Important To make sure you can successfully run the latest versions of the example scripts, you have to install the library from source and install some example-specific requirements. Execute the following steps in a new virtual environment:

git clone https://github.com/huggingface/transformers
cd transformers
pip install .
pip install -r ./examples/requirements.txt

When using Tensorflow, TPUs are supported out of the box as a tf.distribute.Strategy.

When using PyTorch, we support TPUs thanks to pytorch/xla. For more context and information on how to setup your TPU environment refer to Google's documentation and to the very detailed pytorch/xla README.

In this repo, we provide a very simple launcher script named xla_spawn.py that lets you run our example scripts on multiple TPU cores without any boilerplate. Just pass a --num_cores flag to this script, then your regular training script with its arguments (this is similar to the torch.distributed.launch helper for torch.distributed).

For example for run_glue:

python examples/xla_spawn.py --num_cores 8 \
	examples/text-classification/run_glue.py
	--model_name_or_path bert-base-cased \
	--task_name mnli \
	--data_dir ./data/glue_data/MNLI \
	--output_dir ./models/tpu \
	--overwrite_output_dir \
	--do_train \
	--do_eval \
	--num_train_epochs 1 \
	--save_steps 20000

Feedback and more use cases and benchmarks involving TPUs are welcome, please share with the community.