why i can't reverse a list of list in python

Question

i wanted to do something like this but this code return list of None (i think it\'s because list.reverse() is reversing the list in place):

map(lambda row: row.r         


        

Answer 1

You can also use a slice to get the reversal of a single list (not in place):

>>> a = [1,2,3,4]
>>> a[::-1]
[4, 3, 2, 1]

So something like:

all_reversed = [lst[::-1] for lst in figure]

...or...

all_reversed = map(lambda x: x[::-1], figure)

...will do what you want.