Quicksort 2

Quicksort2.py

"""Implement quick sort in Python.
Input a list.
Output a sorted list."""
def quicksort(array):
    low = 0
    high = len(array)-1
    partition(array, low, high)
    return array

def partition(array, low, high):
    
    if low >= high:
        return None
    
    pivot = array[high]
    testIndex = low - 1
    
    for i in range(low, high):
        if array[i] <= pivot:
            testIndex = testIndex + 1
            array[testIndex], array [i] = array[i], array[testIndex]
    array[testIndex + 1], array[high] = array[high], array[testIndex + 1]
    
    testIndex = testIndex + 1
    
    partition(array, low, testIndex - 1)
    partition(array, testIndex + 1, high)
    
test = [21, 4, 1, 3, 9, 20, 25, 6, 21, 14]
print quicksort(test)