diff --git a/rce-comm/rce/comm/buffer.py b/rce-comm/rce/comm/buffer.py
index f3580aa..81cf25f 100644
--- a/rce-comm/rce/comm/buffer.py
+++ b/rce-comm/rce/comm/buffer.py
@@ -29,6 +29,7 @@
 #     \author/s: Dhananjay Sathe
 #
 #
+from zope.interface import implements
 
 from autobahn.websocket import WebSocketProtocol
 from collections import defaultdict, deque