问题 I'm working with RNN and using Pytorch & Torchtext. I've got a problem with building vocab in my RNN. My code is as follows: TEXT = Field(tokenize=tokenizer, lower=True) LABEL = LabelField(dtype=torch.float) trainds = TabularDataset( path='drive/{}'.format(TRAIN_PATH), format='tsv', fields=[ ('label_start', LABEL), ('label_end', None), ('title', None), ('symbol', None), ('text_content', TEXT), ]) testds = TabularDataset( path='drive/{}'.format(TEST_PATH), format='tsv', fields=[ ('text_content