python中遍历列表的合并问题

Question

针对爬虫结果的列表，应当如何处理才能进行合并，试过一些方法都不是预期的效果
我希望的效果是将：
【‘犯罪’】
【‘犯罪’，‘剧情’】
……
合并成：
【‘犯罪’，‘犯罪’，‘剧情’……】
最终目的是进行出现频率的统计。
谢谢指点！

Answer 1

Put count_times=[] outside the big loop (the first loop), and then count

print dict([(i,count_times.count(i)) for i in set(count_times)])

Answer 2

If your goal is to count the frequency of occurrence, you can use Counter in collections
As shown in the picture

Answer 3

Just use a dictionary to count

Answer 4

In [1]: b, a = {}, [1, 2, 3, 4, 5, 6]

In [2]: [b.update({key: b[key] + 1}) if key in b.keys() else b.update({key: 1})  for key in a]
Out[2]: [None, None, None, None, None, None]

In [3]: b
Out[3]: {1: 1, 2: 1, 3: 1, 4: 1, 5: 1, 6: 1}

Answer 5

Counter can also display the list after statistics