擅长:python、mysql、java
<p>这将创建一个新的字典列表,所有字典都具有完整的键:</p>
<pre><code>>>> import itertools as it
>>> l = [{'x': 42}, {'x': 23, 'y': 5}]
>>> all_keys = set(it.chain.from_iterable(l))
>>> [dict((k, a.get(k, None)) for k in all_keys) for a in l]
[{'x': 42, 'y': None}, {'x': 23, 'y': 5}]
</code></pre>