Cleanup py2 import code in demo

Author: laggardkernel

demos/file_upload/file_receiver.py

@@ -9,12 +9,7 @@
 """
 
 import logging
-
-try:
-    from urllib.parse import unquote
-except ImportError:
-    # Python 2.
-    from urllib import unquote
+from urllib.parse import unquote
 
 import tornado.ioloop
 import tornado.web

demos/file_upload/file_uploader.py

@@ -13,14 +13,9 @@
 import os
 import sys
 from functools import partial
+from urllib.parse import quote
 from uuid import uuid4
 
-try:
-    from urllib.parse import quote
-except ImportError:
-    # Python 2.
-    from urllib import quote
-
 from tornado import gen, httpclient, ioloop
 from tornado.options import define, options