best way to use inline for loop in lists and flat the result in python

Question

I have a list of dictionaries and in each of the dictionaries, I have a property that contains a list of ids. so I need to get the content of my properties as a new list . I tried to do this by inline for loop syntax . but I get this result :

my_list  = [{"sessions": [1,2,3,42,56]}, {"sessions": [1,52,53,4,55]},{"sessions": [1,4,5]}]
listed_sessions =[ s for s in [j["sessions"] for j in my_list for item in j]]

print(listed_sessions)

result :

[[1, 2, 3, 42, 56], [1, 52, 53, 4, 55], [1, 4, 5]]

I mixed two different for loop as you can see. but I need to know, how can I get my result in a flat list?

@AsafS. tnx but I already used two for-loop ,I need to know where is my problem I can't get my result as i expected — Babak Abadkheir, Sep 05 '20 at 06:35
Please see https://treyhunner.com/2015/12/python-list-comprehensions-now-in-color/ — Karl Knechtel, Sep 05 '20 at 06:45

score 2 · Accepted Answer · answered Sep 05 '20 at 06:45

2

listed_sessions =[j for item in my_list for j in item["sessions"]]

answered Sep 05 '20 at 06:45

AlexisG

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best way to use inline for loop in lists and flat the result in python

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