Update files from the datasets library (from 1.6.1)

Release notes: https://github.com/huggingface/datasets/releases/tag/1.6.1

trec.py

@@ -155,7 +155,7 @@ class Trec(datasets.GeneratorBasedBuilder):
         ]
 
     def _generate_examples(self, filepath):
-        """ Yields examples. """
+        """Yields examples."""
         # TODO: Yields (key, example) tuples from the dataset
         with open(filepath, "rb") as f:
             for id_, row in enumerate(f):