Mathy: The math teacher

import urllib
import urllib2
import re
import json

def lambda_handler(event, context):
    
    if (event['session']['application']['applicationId'] != "amzn1.ask.skill.dae3422d-d32d-xxxx-xxxx-e2dc1986608e"):
        raise ValueError("Invalid Application ID")
    
    url = 'http://api.wolframalpha.com/v2/query'
    
    values = {'appid' : 'XXXXXX-XXXXXXXXXX',
              'input' : event['request']['intent']['slots']['Problem']['value']}
    
    data = urllib.urlencode(values)
    req = urllib2.Request(url, data)
    response = urllib2.urlopen(req)
    response = response.read()
    response = str(re.findall(r'<plaintext>(.*)?</plaintext>', response))
    
    session_attributes = {}
    card_title = "Alexa My Math Teacher"
    speech_output = "The answer is " + response
    reprompt_text = ""
    should_end_session = True
    
    return build_response(session_attributes, build_speechlet_response(
        card_title, speech_output, reprompt_text, should_end_session)) 
    
def build_speechlet_response(title, output, reprompt_text, should_end_session):
    return {
        "outputSpeech": {
            "type": "PlainText",
            "text": output
        },
        "card": {
            "type": "Simple",
            "title": title,
            "content": output
        },
        "reprompt": {
            "outputSpeech": {
                "type": "PlainText",
                "text": reprompt_text
            }
        },
        "shouldEndSession": should_end_session
    }

def build_response(session_attributes, speechlet_response):
    return {
        "version": "1.0",
        "sessionAttributes": session_attributes,
        "response": speechlet_response
    }