我在hortonworks数据平台2.2上使用spark，我得到以下错误…有什么想法吗？

# !/usr/bin/env python
import sys
import pyspark
from pyspark import SparkContext
if 'sc' not in globals():
    #sc = SparkContext('local[4]', 'pyspark','map')
    sc = SparkContext(appName="PythonKMeans")
nums = sc.map([23,232,1,232,43,43])
squared = nums.map(lambda x: x*x).collect()
for num in squared:
    print num