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james john
Courses Plus Student 193 PointsMake a function name first_and_last_4 that accepts an iterable and returns the first 4 and last 4 items
why doesn't this function give me the first and the last 4 ?
def first_and_last_4(item):
list_1 = item[0:4] + item[-1:-5:-1]
list_2 = list_1.sort()
return list_2
3 Answers
Nicholas Ah Kun
2,419 Pointsalso for list_1 remember that you don't need a start position if you're getting the first 4.
And to go 'backwards' through a list just use a -, you don't need a negative stepping. I.e. item[-4:] tells python to go 4 places from the back of the list, to the end of the list.
Dan Johnson
40,532 PointsThe sort method doesn't return a value, it sorts the calling list in place. You won't have to use list_2 to save the result.
Giovanni Cortes
iOS Development Techdegree Student 4,803 PointsIs easy if you use the + and len() operators with the list.
You can create two list with the same list, the list1 that you are using is correct. The second one is:
- You need to start with the last 4 digits of the list, so, how I obtain it? You need to know the length of the list and subtract 4 elements.
- Continue until the end of the list
- Add the first list and the second list