Dataset Preparation Error

[Kojo7]

  File "prepare_datasets.py", line 21, in <module>
    translation_dataset = TranslationDataset(args.save_data_dir, 'train')
  File "/home/transformer-pytorch/datasets.py", line 56, in __init__
    source, target = line.strip().split('\t')
ValueError: not enough values to unpack (expected 2, got 1)

I get this error above even though I have the datasets in the right formats;

• src-train.txt
• tgt-train.txt
• src-val.txt
• tgt-val.txt

Is there something I'm doing wrong, help please.

Thanks