pad_token_box (`List[int]`, *optional*, defaults to `[0, 0, 0, 0]`):
            The bounding box to use for the special [PAD] token.
        pad_token_label (`int`, *optional*, defaults to -100):
            The label to use for padding tokens. Defaults to -100, which is the `ignore_index` of PyTorch's
            CrossEntropyLoss.
        only_label_first_subword (`bool`, *optional*, defaults to `True`):
            Whether or not to only label the first subword, in case word labels are provided.
    )