need itertools

generic_conll.py

@@ -2,7 +2,7 @@
 # Lint as: python3
 
 import os
-
+import itertools
 import datasets
 
 
@@ -61,7 +61,7 @@ class Conll(datasets.GeneratorBasedBuilder):
         return splits
 
     def _generate_examples(self, files):
-        for filepath in files:
+        for file_idx, filepath in enumerate(itertools.chain.from_iterable(files)):
             logger.info("⏳ Generating examples from = %s", filepath)
             with open(filepath, encoding="utf-8") as f:
                 guid = 0