def __init__(self,
                 data_root,
                 image_root,
                 text_type,
                 image_type,
                 **kwargs):
        """
        For ViLBERT pretrained
        Two task:
            1. masked multi-modal modelling
            2. multi-modal alignment prediction
        Args:
        :param text_type: token, bert
        :param image_type: raw, region
        """
        super().__init__(data_root,
                         image_root,
                         text_type,
                         image_type,
                         **kwargs)

        For ViLBERT pretrained
        Two task:
            1. masked multi-modal modelling
            2. multi-modal alignment prediction
        Args:
        :param text_type: token, bert
        :param image_type: raw, region
        
torchmm/datasets/pretrain_dataset.py