python - flatten list of lists of lists to a list of lists

Question

I've already searched SO for how to flatten a list of lists (i.e. here:Making a flat list out of list of lists in Python) but none of the solutions I find addresses flattening a list of lists of lists to just a list of lists.

I have:

my_list = [ [ [1,2,3],[4,5] ], [ [9],[8,9,10],[3,4,6] ], [ [1] ] ]

I want:

my_list = [ [1,2,3,4,5], [9,8,9,10,3,4,6], [1] ]

The solution should work for a list of floats as well. Any suggestions?

Answer 1

If we apply the logic from this answer, should not it be just:

In [2]: [[item for subsublist in sublist for item in subsublist] for sublist in my_list]
Out[2]: [[1, 2, 3, 4, 5], [9, 8, 9, 10, 3, 4, 6], [1]]

And, similarly via itertools.chain():

In [3]: [list(itertools.chain(*sublist)) for sublist in my_list]
Out[3]: [[1, 2, 3, 4, 5], [9, 8, 9, 10, 3, 4, 6], [1]]