    def load_vocabulary(filepath,
                        unk_token=None,
                        pad_token=None,
                        bos_token=None,
                        eos_token=None,
                        **kwargs):
        """
        Builds the :class:`Vocab` from a file reserving all tokens by calling
        :meth:`Vocab.from_dict` method. The file contains a token per line, and
        the line index would be the index of corresponding token.

        Args:
            filepath (str): the path of file to construct vocabulary.
            unk_token (str, optional): special token for unknown token. If no
                need, it also could be None. Default: None.
            pad_token (str, optional): special token for padding token. If no
                need, it also could be None. Default: None.
            bos_token (str, optional): special token for bos token. If no need,
                it also could be None. Default: None.
            eos_token (str, optional): special token for eos token. If no need,
                it also could be None. Default: None.

            kwargs (dict): Keyword arguments ending with `_token`. It can be
                used to specify further special tokens that will be exposed as
                attribute of the vocabulary and associated with an index.

        Returns:
            Vocab: An instance of :class:`Vocab` generated from the given file.

        Example:
            .. code-block:: python

                from paddlenlp.data import Vocab
                # The vocab file. The sample file can be downloaded firstly.
                # wget https://bj.bcebos.com/paddlenlp/data/senta_word_dict.txt
                vocab_file_path = './senta_word_dict.txt'
                # Initialize the Vocab
                vocab = Vocab.load_vocabulary(
                    vocab_file_path,
                    unk_token='[UNK]',
                    pad_token='[PAD]')
                print(len(vocab))
                # 1256608
        """
        token_to_idx = {}
        with io.open(filepath, 'r', encoding='utf-8') as f:
            for index, line in enumerate(f):
                token = line.rstrip('\n')
                token_to_idx[token] = int(index)
        vocab = Vocab.from_dict(
            token_to_idx,
            unk_token=unk_token,
            pad_token=pad_token,
            bos_token=bos_token,
            eos_token=eos_token,
            **kwargs)
        return vocab
Builds the :class:`Vocab` from a file reserving all tokens by calling
:meth:`Vocab.from_dict` method. The file contains a token per line, and
the line index would be the index of corresponding token.

Args:
filepath (str): the path of file to construct vocabulary.
unk_token (str, optional): special token for unknown token. If no
need, it also could be None. Default: None.
pad_token (str, optional): special token for padding token. If no
need, it also could be None. Default: None.
bos_token (str, optional): special token for bos token. If no need,
it also could be None. Default: None.
eos_token (str, optional): special token for eos token. If no need,
it also could be None. Default: None.

kwargs (dict): Keyword arguments ending with `_token`. It can be
used to specify further special tokens that will be exposed as
attribute of the vocabulary and associated with an index.

Returns:
Vocab: An instance of :class:`Vocab` generated from the given file.

Example:
.. code-block:: python

from paddlenlp.data import Vocab
# The vocab file. The sample file can be downloaded firstly.
# wget https://bj.bcebos.com/paddlenlp/data/senta_word_dict.txt
vocab_file_path = './senta_word_dict.txt'
# Initialize the Vocab
vocab = Vocab.load_vocabulary(
vocab_file_path,
unk_token='[UNK]',
pad_token='[PAD]')
print(len(vocab))
# 1256608
ptstructure/vqa/pytorchnlp/data/vocab.py