def cat(keypoints_list: List["Keypoints"]) -> "Keypoints":
        """
        Concatenates a list of Keypoints into a single Keypoints

        Arguments:
            keypoints_list (list[Keypoints])

        Returns:
            Keypoints: the concatenated Keypoints
        """
        assert isinstance(keypoints_list, (list, tuple))
        assert len(keypoints_list) > 0
        assert all(isinstance(keypoints, Keypoints) for keypoints in keypoints_list)

        cat_kpts = type(keypoints_list[0])(
            torch.cat([kpts.tensor for kpts in keypoints_list], dim=0)
        )
        return cat_kpts

        Concatenates a list of Keypoints into a single Keypoints

        Arguments:
            keypoints_list (list[Keypoints])

        Returns:
            Keypoints: the concatenated Keypoints
        
video_chat_text/video_chat_with_StableLM/models/grit_src/third_party/CenterNet2/detectron2/structures/keypoints.py