List index out of range error in splunk API call - api

Question

I am trying to get the result of a search query from splunk. But when i try to get the session key, i am getting the following error.
Traceback (most recent call last):
File "splunkenter.py", line 18, in <module>
sessionkey = minidom.parseString(servercontent).getElementsByTagName('sessionKey')[0].childNodes[0].nodeValue
IndexError: list index out of range
splunkenter.py:
import urllib
import httplib2
import time
import re from time
import localtime,strftime
from xml.dom import minidom
import json
baseurl = 'abc.haihd.com:8000'
username = 'xxxxx'
password = 'xxxxx'
myhttp = httplib2.Http()
#Step 1: Get a session key
servercontent = myhttp.request(baseurl + '/services/auth/login', 'POST', headers={}, body=urllib.urlencode({'username':username, 'password':password}))[1]
sessionkey =
minidom.parseString(servercontent).getElementsByTagName('sessionKey')[0].childNo‌​des[0].nodeValue
print "====>sessionkey: %s <====" % sessionke
Can anybody tell me where is the problem lying. I am very new to API's.