(self, dataset, batch_size, batch_by_tokens, max_src_length, max_tgt_length, buffer_multiple_size,
device, model_path, len_diff=-1, len_ratio=-1, multi_scale=1, corpus="train",
bucket_data=True, rank=-1, num_replicas=0)
source not stored for this graph (policy: none)
nothing calls this directly
no test coverage detected