Quick fix that got inadvertently removed a few days ago

  correctly outputs input_ids and attention_mask."""

  from deepchem.feat.bert_tokenizer import BertFeaturizer

  from transformers import BertTokenizerFast

  sequence = [

  sequences = [

      '[CLS] D L I P T S S K L V [SEP]', '[CLS] V K K A F F A L V T [SEP]'

  ]

  sequence_long = ['[CLS] D L I P T S S K L V V K K A F F A L V T [SEP]']

  tokenizer = BertTokenizerFast.from_pretrained(

      "Rostlab/prot_bert", do_lower_case=False)

  featurizer = BertFeaturizer(tokenizer)

  feats = featurizer(sequence)

  feats = featurizer(sequences)

  long_feat = featurizer(sequence_long)

  assert (len(feats) == 2)

  assert (all([len(f) == 3 for f in feats]))