diff --git a/tools/repo_pull/repo_patch.py b/tools/repo_pull/repo_patch.py
index e2a0453fc..c5367ca8c 100755
--- a/tools/repo_pull/repo_patch.py
+++ b/tools/repo_pull/repo_patch.py
@@ -23,6 +23,7 @@ from __future__ import print_function
 
 import argparse
 import os
+import sys
 
 from gerrit import (
     create_url_opener_from_args, find_gerrit_name, query_change_lists, get_patch