From c79de3ab3c7531ab6d45c8c92b6ada0c620daf09 Mon Sep 17 00:00:00 2001
From: SomberNight <somber.night@protonmail.com>
Date: Fri, 16 Mar 2018 22:06:38 +0100
Subject: [PATCH] fix #4139

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

diff --git a/lib/network.py b/lib/network.py
index 872e96f78..d40951fde 100644
--- a/lib/network.py
+++ b/lib/network.py
@@ -563,7 +563,7 @@ class Network(util.DaemonThread):
                 self.notify('fee')
         elif method == 'blockchain.relayfee':
             if error is None:
-                self.relay_fee = int(result * COIN)
+                self.relay_fee = int(result * COIN) if result is not None else None
                 self.print_error("relayfee", self.relay_fee)
         elif method == 'blockchain.block.get_chunk':
             self.on_get_chunk(interface, response)