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Python Functional Python Functional Workhorses Map

Andy McDonald
Andy McDonald
Python Development Techdegree Student 6,418 Points

Trouble counting backwards

I don't understand why my code isn't counting backwards.

backwards = [
    [5, 4, 3, 2, 1],
def reverse(var):
    answer =[]
    for itera in var:
        for i in range(len(itera), -1):
    answer = "".join(answer)
    return answer


1 Answer

Steven Parker
Steven Parker
217,533 Points

Here are a few hints:

  • the instructions ask for a function "that takes a single iterable item", not all of them at once
  • the function only needs to return the result, it doesn't need to print anything
  • in a range, you must specify a "stop" value along with a "step"
  • this code mismatches lists and strings, you might want to convert (split) the string first
  • do you remember slices? They might provide an even easier way to do this task