diff --git a/sanic/response.py b/sanic/response.py
index e3c7249d..2f5c0135 100644
--- a/sanic/response.py
+++ b/sanic/response.py
@@ -1,4 +1,3 @@
-from collections import ChainMap
 from mimetypes import guess_type
 from os import path
 from ujson import dumps as json_dumps