fix issue

kenwoodjw · kenwoodjw · commit 1ff99df1818d · 2019-03-05T17:24:17.000+08:00
diff --git a/README.md b/README.md
@@ -356,7 +356,7 @@
                 dict1[key] = value
         return dict1
 ```
-## 3.5 请按alist中元素的age由小到大排序
+## 3.5 请按alist中元素的age由大到小排序
 ```
     alist = [{'name':'a','age':20},{'name':'b','age':30},{'name':'c','age':25}]
     def sort_by_age(list1):
