main loop 'builtin_function_or_method' object is not iterable

import urllib2
 import time
 import datetime
 
 stocksToPull = 'AAPL','GOOG','MSFT','CMG','AMZN','EBAY','TSLA'
 
 def pullData(stock):
  try:
  print 'Currently pulling',stock
  print str(datetime.datetime.fromtimestamp(time.time()).strftime('%Y-%m-%d %H:%M:%S'))
  urlToVisit = 'http://chartapi.finance.yahoo.com/instrument/1.0/'+stock+'/chartdata;type=quote;range=5d/csv'
  saveFileLine = stock+'.txt'
 
  try:
  readExistingData = open(saveFileLine,'r').read()
  splitExisting = readExistingData.split('\n')
  mostRecentLine = splitExisting[-2]
  lastUnix = mostRecentLine.split(',')[0]
  except:
  lastUnix = 0
 
  saveFile = open(saveFileLine,'a')
  sourceCode = urllib2.urlopen(urlToVisit).read()
  splitSource = sourceCode.split
 
  for eachLine in splitSource:
  splitLine = eachLine.split(',')
  if len(splitLine) ==6:
  if splitLine[0] > lastUnix:
  if 'values' not in eachLine:
  lineToWrite = eachLine+'\n'
  saveFile.write(lineToWrite)
 
  saveFile.close()
 
  print 'Pulled',stock
  print 'sleeping...'
  print str(datetime.datetime.fromtimestamp(time.time()).strftime('%Y-%m-%d %H:%M:%S'))
  time.sleep(300)
 
  except Exception,e:
  print 'main loop',str(e)
 
 for eachStock in stocksToPull:
  pullData(eachStock)