fix lint

Author: jreback

pandas/core/frame.py

@@ -1833,7 +1833,7 @@ def info(self, verbose=None, buf=None, max_cols=None, memory_usage=None,
         def _verbose_repr():
             lines.append('Data columns (total '
                          '{count} columns):'.format(count=cols_count))
-            space = max([len(pprint_thing(k)) for k in cols])
+            space = max((len(pprint_thing(k)) for k in cols))
             space = max(space, len(pprint_thing('Column'))) + 4
             space_num = len(pprint_thing(cols_count))
             space_num = max(space_num, len(pprint_thing('Index'))) + 2