fix

dogs-video-object-tracking-dataset.py

@@ -83,6 +83,7 @@ class DogsVideoObjectTrackingDataset(datasets.GeneratorBasedBuilder):
         masks = dl_manager.download_and_extract(f"{_DATA}{self.config.name}_masks.zip")
         annotations = dl_manager.download(f"{_DATA}{self.config.name}.xml")
         images = dl_manager.iter_files(images)
+        masks = dl_manager.iter_files(masks)
         return [
             datasets.SplitGenerator(
                 name=datasets.Split.TRAIN,