Quicksort in Python

# Easy, single parameter method call to get the method going.
def quickSort(arr):
   quickSortAux(arr, 0, len(arr))

# Actual quicksort algorithm
def quickSortAux(arr, low, high):
   if low < high:
       # Partition the array
       p = partition(arr, low, high)
       # Sort the left half
       quickSortAux(arr, low, p - 1)
       # Sort the right half
       quickSortAux(arr, p + 1, high)

# Partition 
def partition(arr, low, high):
   # Pick a pivot
   pivot = arr[high]
   i = low
   # If a number is less than the pivot, put it on the left
   # if more, put it on the right
   for j in range(low, high):
       if arr[j] < pivot:
           swap(arr, i, j)
           i += 1
   swap(arr, i, high)
   return i

# Auxiliary swap method
def swap(arr, a, b):
   tmp = arr[a]
   arr[a] = arr[b]
   arr[b] = tmp