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How to Sort Using Heap Sort in Python?

Here is how to sort using Heap Sort in Python?
Run the code here: https://repl.it/@VinitKhandelwal/heap-sort
def max_heapify(A, heap_size, i):
left = 2 * i + 1
right = left + 1
largest = i
if left < heap_size and A[left] > A[largest]:
largest = left
if right < heap_size and A[right] > A[largest]:
largest = right
if largest != i:
A[i], A[largest] = A[largest], A[i]
max_heapify(A, heap_size, largest)

def build_heap(A):
heap_size = len(A)
for i in range (int(heap_size/2),-1,-1):
max_heapify(A, heap_size, i)

def heapsort(A):
heap_size = len(A)
build_heap(A)
#print A #uncomment this print to see the heap it builds
for i in range(heap_size-1,0,-1):
A[0], A[i] = A[i], A[0]
heap_size -= 1
max_heapify(A, heap_size, 0)

A = [2,8,1,4,14,7,16,10,9,3]
heapsort(A)
print(A)

OUTPUT

[1, 2, 3, 4, 7, 8, 9, 10, 14, 16]

TIME COMPLEXITY

O(n log n)

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