Vocabulary named target

[laomagic]

Describe the bug File "/home/serverai/anaconda3/envs/yanGPU/lib/python3.6/site-packages/fastNLP/io/data_bundle.py", line 100, in get_vocab raise KeyError(error_msg) KeyError: "DataBundle do NOT have Vocabulary named target. It should be one of dict_keys(['vocab'])."

To Reproduce def get_vocab(self, field_name: str) -> Vocabulary: r""" 获取field名为field_name对应的vocab

    :param str field_name: 名称
    :return: Vocabulary
    """
    if field_name in self.vocabs.keys():
        return self.vocabs[field_name]
    else:
        error_msg = f'DataBundle do NOT have Vocabulary named {field_name}. ' \
                    f'It should be one of {self.vocabs.keys()}.'
        logger.error(error_msg)
        raise KeyError(error_msg)

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[yhcc]

就是data_bundle中的Vocabulary被设置成了vocab这个名称，而不是target，所以需要data_bundle.get_vocab('vocab')这样获取。如果是的确是有一个target的vocab的话，在data_bundle创建的时候需要通过 data_bundle.set_vocab(vocab=target_vocab, name='target')这样先设置才能在之后获取到。