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Python Functional Python Functional Workhorses Map

David Hernandez
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David Hernandez
Python Development Techdegree Graduate 12,180 Points

unable to create a function that reverses

I keep getting an error that says reverse didn't accept an argument, however, if I run it locally it works just fine.

from copy import copy

backwards = [
    [5, 4, 3, 2, 1],

def reverse(items):
    items = copy(items)
    return [item[::-1] for item in items]

1 Answer

Jeff Muday
Jeff Muday
Treehouse Moderator 28,372 Points

I can see from your code you understood how to reverse an array. Good job!

It is a little simpler than you expected.

def reverse(items)
    return items[::-1]

Now, for the second part of the Challenge, you are going to use reverse as a reference to the function in Part 1. And map() to assign a new variable forwards

forwards = map(reverse, backwards)

The wording is a little bit awkward, but you get the gist of it!