Check multi-index list encode for multilabels

NIH-Chest-X-ray-dataset.py

@@ -144,6 +144,7 @@ class XChest(datasets.GeneratorBasedBuilder):
 		        yield i, {
 			    "image_file_path": path,
 			    "image": path,
-			    "labels": ["Mass", "Hernia"]
+			    #"labels": ["Mass", "Hernia"]
+			    "labels": [5, 14]
 			}