diff --git a/luigi/requirements.txt b/luigi/requirements.txt
old mode 100755
new mode 100644
index 74dca85..402c71f
--- a/luigi/requirements.txt
+++ b/luigi/requirements.txt
@@ -21,7 +21,7 @@ gem==1.0.0
 gpg==1.10.0
 h5py==2.7.1
 html5lib==0.9999999
-httplib2==0.9.2
+httplib2==0.18.0
 idna==2.6
 jedi==0.11.1
 Jinja2==2.10