Copied example does not working in IDLE, python

I am trying to learn python for Machine Learning and I just copied an example from the test book to my IDEL program. Here is the code, copied from here

from numpy import *
import operator

def createDataSet():
    group = array([[1.0,1.1], [1.0,1.0], [0,0], [0,0.1]])
    labels = ['A','A','B','B']
    return group, labels

def classify0(inX, dataSet, labels, k):
    dataSetSize = dataSet.shape[0]

    diffMat = tile(inX, (dataSetSize,1)) - dataSet
    sqDiffMat = diffMat ** 2
    sqDistances = sqDiffMat.sum(axis = 1)
    distances = sqDistances ** 0.5

    sortedDistIndicies = distances.argsort()

    # Voting with lowest k distances
    classCount={}
    for i in range(k):
        voteIlabel = labels[sortedDistIndicies[i]]
        classCount[voteIlabel] = classCount.get(voteIlabel, 0) + 1

    # Decompose into a list of tuples and sort by second item
    sortedClassCount = sorted(classCount.iteritems(),
        key=operator.itemgetter(1), reverse=True)

    return sortedClassCount[0][0]

group, labels = createDataSet()
classify0([0,0], group, labels, 3)

Then I compel it in IDLE but I am keep getting the following error message in Python Shell. (I am using version 3.4.3)

The error message is:

Traceback (most recent call last):
  File "/Users/Python/KNN.py", line 32, in <module>
    classify0([0,0], group, labels, 3)
  File "/Users/Python/KNN.py", line 26, in classify0
    sortedClassCount = sorted(classCount.itemgetter(),
AttributeError: 'dict' object has no attribute 'itemgetter'

I just don't understand why this is not working...and I don't even see where this 'dict' object is...Please help!