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Python Functional Python Functional Workhorses Map

Posted by Olivia Cooksey
Olivia Cooksey
5,284 Points

backwards = [ 'tac', 'esuoheerT', 'htenneK', [5, 4, 3, 2, 1], ]

Please see why this will not work and help solve.

maps.py 
backwards = [
    'tac',
    'esuoheerT',
    'htenneK',
    [5, 4, 3, 2, 1],
]

def reverse(y):
    y.reverse() 
    return y

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

This would work on a list, but the goal is to reverse any kind of iterable including strings. And strings don't have a reverse() method, so you can't count on being able to call y.reverse().

Hint: any iterable can be slice‍d, and the optional step value can also control the direction.