from xml.etree import ElementTree as ET
import urllib2
import base64

username = ""
password = ""

request = urllib2.Request("https://my.plexapp.com/users/sign_in.xml","")
base64string = base64.encodestring('%s:%s' % (username, password)).replace('\n', '')
request.add_header("Authorization", "Basic %s" % base64string)
request.add_header("X-Plex-Client-Identifier", "VoxCommando")
xmlResult = urllib2.urlopen(request)

resultSTR = xmlResult.read()
#print resultSTR

tree = ET.ElementTree(ET.fromstring(resultSTR))
root = tree.getroot()
#for user in root.findall('user'):
#       authID=user.get('authentication-token')
#       print authID

result=root.find('authentication-token').text