擅长:python、mysql、java
<p>以下是defaultdict的一种方法:</p>
<pre><code>from collections import defaultdict
combined = defaultdict(list)
lst = [{'City or Community': 'Augusta', 'State':'GA', 'Parent Company': 'WoW!'},
{'City or Community': 'Augusta', 'State':'GA', 'Parent Company': 'Comcast'},]
# Loop through your list of dictionaries and
# create a combined dictionary where keys are cities and states, and values are lists of companies
for d in lst:
combined[(d['City or Community'], d['State'])].append(d['Parent Company'])
# For each of the keys in the combined dictionary, only print them out
# if there are more than one companies for that key
print(list(cityAndState for (cityAndState, companies) in combined.items() if len(companies) > 1))
>>> [('Augusta', 'GA')]
</code></pre>