src/transformers/models/maskformer/convert_maskformer_original_pytorch_checkpoint_to_pytorch.py/TrackedStateDict/diff
class TrackedStateDict:    def diff(self) -> List[str]:
        """This method returns a set difference between the keys in the tracked state dict and the one we have access so far.
        This is an effective method to check if we have update all the keys

        Returns:
            List[str]: List of keys not yet updated
        """
        return set(self.to_track.keys()) - self._seen