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# reverse_events

```def reverse_evens(iterable):
return iterable[::-2]

print reverse_evens([1,2,3,4,5])
# this line was not typed in the challenge.
#Added this to check the result in an online python compiler
```

This code prints out the required list: [5, 3, 1]. Why does the challenge say that it is a mistake? Maybe I misunderstood the task? Thanks in advance for you kind and swift reply.

slices.py
```def first_4(iterable):
return iterable[0:4]

def first_and_last_4(iterable):
return first_4(iterable) + iterable[-4:]

def odds(iterable):
return iterable[1::2]

def reverse_evens(iterable):
return iterable[::-2]
```

## You're not accounting for the possibility of different list lengths.

This approach will only work on lists that have an odd number of items. If the list passed to the function has an even number of items, this will return reverse odds instead of reverse evens.

You'll either need to calculate the starting position based on the list size, or you'll need to extract the evens first and then reverse them in a separate step.

Thanks for your swift reply. I checked whether the length of the iterable is even or odd and looped through the list accordingly and it worked!!!

You don't actually need a loop, it would be better to use slices since this is a slice challenge.

You got it right. By a 'loop' I meant taking every second item from the end like this:

iterable[::-2]

This is called a slice in Python, isn't it? However, since Python is built on "C" and it is only a built in function, behind the scenes this must work like a backward loop)) don't you think?

You're probably right about what goes on in the engine, but from a programming perspective, that's simply called a "slice". So I'm guessing when you say you "looped through the list accordingly" you mean "sliced the list with different arguments".