Transformers to list, when split is None

      input_files=[dataset_file], shard_size=10000, data_dir=save_folder)

  if split is None:

    transformer = dc.trans.NormalizationTransformer(

    transformer = [

        dc.trans.NormalizationTransformer(

            transform_X=False, transform_y=True, dataset=dataset)

    ]

    logger.info("Split is None, about to transform dataset.")

    for transformer in transformers:

      dataset = transformer.transform(dataset)

    return chembl25_tasks, (dataset, None, None), transformers

      'scaffold': dc.splits.ScaffoldSplitter(),

  }

  logger.info("About to split data.")

  logger.info("About to split data with {} splitter.".format(split))

  splitter = splitters[split]

  train, valid, test = splitter.train_valid_test_split(dataset, seed=split_seed)