Python Data Structure nth item code error-CodePudding

I wrote some code and it's not running correctly. It's supposed to follow the example. Can someone help me figure out what I did wrong? Thank you.

    >>> nth_item(['one', 'two', 'three'], 1)
    'one'
    >>> nth_item(['one', 'two', 'three'], 3)
    'three'
    >>> nth_item(['one', 'two', 'three'], 0)
    >>> nth_item(['one', 'two', 'three'], -1)
    >>> nth_item(['one', 'two', 'three'], 1, reverse=True)
    'three'

def nth_item(item_list, n, reverse=False):
    length = len(item_list)
    if n < 1 or n > length:
        return None
    if reverse:
        return item_list[length-n]
    return item_list[n-1]
    pass

CodePudding user response：

I run the same function and parse the return values into multiple variables (a,b,c,d,e). I only removed the pass statement as it would never be used.

def nth_item(item_list, n, reverse=False):
    length = len(item_list)
    if n < 1 or n > length:
        return None
    if reverse:
        return item_list[length-n]
    return item_list[n-1]


# run the function
a = nth_item(['one', 'two', 'three'], 1)
b = nth_item(['one', 'two', 'three'], 3)
c = nth_item(['one', 'two', 'three'], 0)
d = nth_item(['one', 'two', 'three'], -1)
e = nth_item(['one', 'two', 'three'], 1, reverse=True)


# show results
print(a)
print(b)
print(c)
print(d)
print(e)

and these are the results:

one
three
None
None
three

This works fine, so were you expecting something different ?