How do I concatenate two lists inside nested list Python?

Ada :

How do I concatenate two lists inside the nested list Python?

I have this list

lists_of_lists =[[[1],[2]],[[3],[5]],[[6],[6]]]

And my expected output is

lists_of_lists =[[1,2],[3,5],[6,6]]

I tried this way

new = []
lists_of_lists =[[[1],[2]],[[3],[5]],[[6],[6]]]
for i in range(len(lists_of_lists)):
    for list in  lists_of_lists[i]:
        for element in list:
            new.append(element)
print(new)

But I got

[1, 2, 3, 5, 6, 6]

Thank you for any suggestions

r.ook :

[[i for inner in sub_lists for i in inner] for sub_lists in lists_of_lists]

# [[1, 2], [3, 5], [6, 6]]