擅长:python、mysql、java
<p>用列表理解法尽可能缩短答案。我确信有一种方法可以将函数缩减为一行。在</p>
<pre><code>def new_dict(rating):
my_dict = dict([(i,[]) for i in set([value for key,value in rating.items()])])
[my_dict[value].append(key) for key,value in rating.items()]
return my_dict
rating = {"bob": "excellent", "barnum": "passing", "beatrice": "satisfactory", "bernice": "passing", "ben": "no pass", "belle": "excellent", "bill": "passing", "bernie": "passing", "baxter": "excellent"}
print(new_dict(rating)) # new_dict is the function
</code></pre>
<p>这将打印以下输出:</p>
^{pr2}$