Use urleconde from a library that works with python 2.7 and 3

Author: alexisluque

01-Login/server.py

@@ -1,11 +1,7 @@
 """Python Flask WebApp Auth0 integration example
 """
 from functools import wraps
-import six
-if six.PY3:
-    from urllib.parse import urlencode
-else:
-    from urllib import urlencode
+from six.moves.urllib.parse import urlencode
 from os import environ as env
 from dotenv import load_dotenv, find_dotenv
 from flask import Flask