BUG: fix featurizer NamerError in benchmark_curve.py

      if pair in CheckFeaturizer:

        featurizer = CheckFeaturizer[pair][0]

        n_features = CheckFeaturizer[pair][1]

      else:

        supported_combinations = [key for key in CheckFeaturizer.keys() if pair[0] == key[0]]

        print(supported_combinations)

        supported_models = [k[1] for k in supported_combinations] 

        raise ValueError(

          "Model %s not supported for %s dataset. Please choose from the following:\n%s"

          % (pair[1], pair[0], " ".join(supported_models)))

      tasks, all_dataset, transformers = load_dataset(

          dataset, featurizer, split='index')