clean formatting

Author: Nico Cernek

pandas/core/reshape/merge.py

@@ -1282,6 +1282,7 @@ def _get_join_indexers(left_keys, right_keys, sort=False, how="inner", **kwargs)
 
     # bind `sort` arg. of _factorize_keys
     fkeys = partial(_factorize_keys, sort=sort)
+
     # get left & right join labels and num. of levels at each location
     llab, rlab, shape = map(list, zip(*map(fkeys, left_keys, right_keys)))