How to decode the message at the end of Google Foobar

foobar.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import base64

MESSAGE = '''
EUYQGhMMSx0cU0FIU1MCFAQPG01NQ0gTAEICChUGBxZTRVxBSQoZFQYKHQpKSUNURhcVEgoUFR1I
SltDSBkBTRwKEAgQHxFCSkFJDgkJCgoGCkMLAQBGUklUQhMPAgAJCgYLV0MOSR0VAxAaABZBQVRP
TRICCRVIAk5IEg4dVFRfRkYZBgRARBI=
'''

KEY = 'jacopo.notarstefano'

result = []
for i, c in enumerate(base64.b64decode(MESSAGE)):
    result.append(chr(ord(c) ^ ord(KEY[i % len(KEY)])))

print ''.join(result)

I got a dictionary after decoding the encrypted text.
It is this -> b"{'success' : 'great', 'colleague' : 'esteemed', 'efforts' : 'incredible', 'achievement' : 'unlocked', 'rabbits' : 'safe', 'foo' : 'win!'}"
what does this mean??

####python2 code

import base64

MESSAGE = '''
EUYQGhMMSx0cU0FIU1MCFAQPG01NQ0gTAEICChUGBxZTRVxBSQoZFQYKHQpKSUNURhcVEgoUFR1I
SltDSBkBTRwKEAgQHxFCSkFJDgkJCgoGCkMLAQBGUklUQhMPAgAJCgYLV0MOSR0VAxAaABZBQVRP
TRICCRVIAk5IEg4dVFRfRkYZBgRARBI=
'''

KEY = 'jacopo.notarstefano'

result = []
for i, c in enumerate(base64.b64decode(MESSAGE)):
result.append(chr(ord(c) ^ ord(KEY[i % len(KEY)])))

print ''.join(result)

i also got same dictionary:
{'success' : 'great', 'colleague' : 'esteemed', 'efforts' : 'incredible', 'achievement' : 'unlocked', 'rabbits' : 'safe', 'foo' : 'win!'}

It's just a final challenge...

I also got this-

{'success' : 'great', 'colleague' : 'esteemed', 'efforts' : 'incredible', 'achievement' : 'unlocked', 'rabbits' : 'safe', 'foo' : 'win!'}

I also got same. in 2016

To visualize decode steps, go to following CyberChef recipe:
https://gchq.github.io/CyberChef/#recipe=From_Base64('A-Za-z0-9%2B/%3D',true)XOR(%7B'option':'Latin1','string':'jacopo.notarstefano'%7D,'Standard',false)&input=RVVZUUdoTU1TeDBjVTBGSVUxTUNGQVFQRzAxTlEwZ1RBRUlDQ2hVR0J4WlRSVnhCU1FvWkZRWUtIUXBLU1VOVVJoY1ZFZ29VRlIxSVNsdERTQmtCVFJ3S0VBZ1FIeEZDU2tGSkRna0pDZ29HQ2tNTEFRQkdVa2xVUWhNUEFnQUpDZ1lMVjBNT1NSMFZBeEFhQUJaQlFWUlBUUklDQ1JWSUFrNUlFZzRkVkZSZlJrWVpCZ1JBUkJJPQ

where can i find the key?