擅长:python、mysql、java
<p>使用<code>dictionary comprehension</code>:</p>
<pre><code>print({k:sum(v)/len(v) for k,v in studentPerf.items()})
</code></pre>
<p>输出:</p>
<pre><code>{('Jeffery', 'male', 'junior'): 0.7749999999999999, ('Able', 'male', 'senior'): 0.8200000000000001, ('Don', 'male', 'junior'): 0.7974999999999999, ('Will', 'male', 'senior'): 0.7975000000000001}
</code></pre>