    def __getitem__(self, idx):
        """slightly modify with if condition to combine train/test."""
        vid, sentence = None, None
        vid = self.data["video_id"].values[idx]
        if "sentence" in self.data:  # for testing.
            sentence = self.data["sentence"].values[idx]
        else:  # for training.
            sentence = vid
        return vid, sentence
slightly modify with if condition to combine train/test.
examples/MMPT/mmpt/processors/dsprocessor.py