fix whitespace a little

json_memoize.py

@@ -7,6 +7,7 @@ import os
 
 
 class HashableDict(dict):
+
     def __hash__(self):
         return hash(tuple(sorted(self.items())))
 
@@ -25,7 +26,6 @@ def json_memoize(filename):
                     json.dump({}, f)
 
         def __call__(self, *args, **kwargs):
-
             with open(filename, "r") as f:
                 memo = json.load(f)
             json_key = repr((self.fn.__name__, args, HashableDict(kwargs)))