Python - Transpose List of Lists of various lengths - 3.3 easiest method

list, nonetype, python, python-3.x, transpose

Solution

You can use `itertools.zip_longest` in Python 3:

>>> from itertools import zip_longest
>>> list(zip_longest(*a))
[(1, 4, 7), (2, 6, 8), (3, None, 9)]

Problem

``` a=[[1,2,3],[4,6],[7,8,9]] ``` In Python 2 If I have a list containing lists of variable lengths then I can do the following: ``` list(map(None,*a)) ``` Result: ``` [(1, 4, 7), (2, 6, 8), (3, None, 9)] ``` In Python 3 None type is seemingly not accepted. Is there, in Python 3, an as simple method for producing the same result.

Original source