text: Title: Tokenizing Dataset Fails with newline or index error
  Body: When trying to tokenize a dataset, it fails with either the error
  `Error: new-line character seen in unquoted field - do you need to open the file in universal-newline mode?`
  or one about list index out of range.
  Running the newest version of the Colab notebook and this happens with both GPT-2 and GPT-Neo.
  
  Please let me know what info is needed or what I can try to fix this.
  
  Thanks!