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Python Python Collections (2016, retired 2019) Slices Slice Functions

Posted by Austin Hales
Austin Hales
4,486 Points

Looking for help with Slices and steps 🙏

Thanks for taking a look. Here is the challenge / objective I am working on:

"Make a new function named first_and_last_4. It'll accept a single iterable but, this time, it'll return the first four and last four items as a single value."

My understanding of this objective is to use two slices of the list; one for the first four value and one for the last four values. Then combine them to satisfy the single value criteria.

The code I wrote which I believe satisfies this is below. The slices seem to pull the first and last four values of any list I test it on but I think it is the single value item I getting tripped up on. I'm not necessarily looking for a solution but more to be pointed in the correct direction. Thanks in advanced!

slices.py 
def first_and_last_4(iterable):
    return iterable[:4] + iterable[-1:-5:-1]

1 Answer

Mark Kastelic
Mark Kastelic
8,147 Points

Hi Austin,

The devil is in the details. Your code does return the first and last 4 values in any list. But, to point you in the "right direction," look carefully at how your last 4 values compare to the original list.

Hope this helps.

Austin Hales
Austin Hales
4,486 Points

Yes! Thank you, Mark! Your response is exactly what I needed. I had a feeling I was overthinking this one. Cheers