Update magpie.py

magpie.py

@@ -122,7 +122,7 @@ class Magpie(datasets.GeneratorBasedBuilder):
                 if len(fields) < 5:
                     fields[1] = True if fields[1] == "yes" else False
                     fields[2] = fields[2].strip().split()
-                    fields[3] = fields[3].strip().split()
+                    fields[3] = fields[3].strip().split() if fields[1] else []
                 else:
                     fields[1] = fields[1].strip().split()
                     fields[-1] = fields[-1].strip().split()