iterative bubble sort

bubble-sort.py

def sort(l):
  for x in range(len(l)-1):
    for i in range(len(l)-(x+1)):
      if l[i] > l[i+ 1]:
        swap(l, i, i+1)
  return l

def swap(l, index1, index2):
 buff = l[index1] 
 l[index1] = l[index2]
 l[index2] = buff

l = [4, 78, 54, 2, 1, 1, 4, 15, 18, 7, 9, 2, 18]

print sort(l)