擅长:python、mysql、java
<p>您可以使用<code>collections.Counter</code>:</p>
<pre><code>>>> dic={'25': {'Return of the Jedi (1983)': 5.0}, '42': {'Batman (1989)': 3.0, 'E.T. the Extra-Terrestrial (1982)': 5.0}, '8': {'Return of the Jedi (1983)': 5.0 }}
>>> from collections import Counter
>>> c=Counter(movie for v in dic.values() for movie in v)
>>> [k for k,v in c.items() if v>1] #returns the name of movies repeated more than once
['Return of the Jedi (1983)']
>>> c
Counter({'Return of the Jedi (1983)': 2,
'Batman (1989)': 1,
'E.T. the Extra-Terrestrial (1982)': 1})
</code></pre>
<p>要获取与每部电影相关的密钥,可以使用<code>collections.defaultdict</code>:</p>
^{pr2}$