index power test mistake

def index_power(array, n):

if len(array) < n:
    return -1 
else:
    len(array) > n
    array[n]**n
    return array[n] ** n

I don't know why this solution has an IndexError at 11 extra test:

"IndexError: list index out of range, indexpower, 7 indexpower((96,92,94), 3)"

Can you explain me this?