don't write to /dev/urandom on Windows platforms

gluon/utils.py

@@ -17,6 +17,7 @@ import random
 import inspect
 import time
 import os
+import sys
 import re
 import logging
 import socket
@@ -299,6 +300,7 @@ def initialize_urandom():
     try:
         os.urandom(1)
         have_urandom = True
+        if sys.platform != 'win32':
             try:
                 # try to add process-specific entropy
                 frandom = open('/dev/urandom', 'wb')