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

Alexander Lausten
Alexander Lausten
3,223 Points

i dont understand number 2 challenge first_and_last_4 as a single value could you please alaborate?

am i supposed to concatenate the list to like this: somelist[:4] + somelist[-1:-5:-1] and return the output list? or add it all together to a "single value" both tells me i did'nt get the it right

please alaborate the challenge for me

def first_4(yourlist):
    return yourlist[:4]

def first_and_last_4(somelist):
    somelist = somelist[:4] + somelist[-1:-5:-1]
    number = ""
    for a in somelist:
        number += a
    return number

2 Answers

Stuart Wright
Stuart Wright
41,118 Points

Just returning the output list is fine - no need to do anything further with it. The problem is that your 'last 4' slice was incorrect. This should do the job:

def first_and_last_4(somelist):
    somelist = somelist[:4] + somelist[-4:]
    return somelist