From fc574ee514c6798ed0950003f1736407e52c2074 Mon Sep 17 00:00:00 2001
From: SomberNight <somber.night@protonmail.com>
Date: Thu, 21 Dec 2017 23:31:59 +0100
Subject: [PATCH] fix #3578

---
 lib/network.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/network.py b/lib/network.py
index 7e7e06bbf..7df6996e8 100644
--- a/lib/network.py
+++ b/lib/network.py
@@ -105,7 +105,8 @@ proxy_modes = ['socks4', 'socks5', 'http']
 def serialize_proxy(p):
     if not isinstance(p, dict):
         return None
-    return ':'.join([p.get('mode'),p.get('host'), p.get('port'), p.get('user'), p.get('password')])
+    return ':'.join([p.get('mode'), p.get('host'), p.get('port'),
+                     p.get('user', ''), p.get('password', '')])
 
 
 def deserialize_proxy(s):