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Python Python Collections (Retired) Slices Slice Functions

Jon Gaspar
Jon Gaspar
656 Points
Posted by Jon Gaspar
Jon Gaspar
656 Points

"Make a function named list_4 that accepts an iterable as an argument and returns the first 4 items in the iterable"

Loving the course so far but can't seem to figure this one out. I tried making a list and using the slice [0:4] thing but that didn't work, then I tried using a 'for' loop which also didn't work, than I tried defining an iterable class (not that I really know that is) but no avail there either.

Any tips? thanks in advance

1 Answer

Evan Demaris
Evan Demaris
64,262 Points

I'm not sure what went wrong with the slice - it helps if you post your code so we can guide you!

That said, you can define your function with a slice as;

def first_four(iterable):
    return iterable[0:4]

Bare in mind for the second and third parts of this challenge; [a:b:c] a is the start, b is the stop, c is the step. You can step backwards with a negative c, you can start so many indexes from the end of a list with a negative a, and you can add slices to each other with a + operator to make a new list from multiple slices of an existing list.