Merge pull request #233 from azanbinzahid/patch-2

Simpler implenentation of map_values snippet

snippets/map_values.md

@@ -5,14 +5,11 @@ tags: dictionary,function,intermediate
 
 Creates a dictionary with the same keys as the provided dictionary and values generated by running the provided function for each value.
 
-- Use `dict.keys()` to iterate over the dictionary's keys, assigning the values produced by `fn` to each key of a new dictionary.
+- Use `dict.items()` to iterate over the dictionary, assigning the values produced by `fn` to each key of a new dictionary.
 
 ```py
 def map_values(obj, fn):
-  ret = {}
-  for key in obj.keys():
-    ret[key] = fn(obj[key])
-  return ret
+  return dict((k, fn(v)) for k, v in obj.items())
 ```
 
 ```py