diff --git a/AUTHORS b/AUTHORS
index 4decac605..df96910d1 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -16,6 +16,7 @@ Gabriel Hurley <gabriel@strikeawe.com>
 Ghe Rivero <ghe@debian.org>
 Greg Althaus <galthaus@austin.rr.com>
 Hengqing Hu <hudayou@hotmail.com>
+Ionuț Arțăriși <iartarisi@suse.cz>
 Ivan Kolodyazhny <e0ne@e0ne.info>
 Jake Dahn <jake@ansolabs.com>
 Jake Zukowski <jake@ponyloaf.com>
diff --git a/horizon/dashboards/settings/ec2/forms.py b/horizon/dashboards/settings/ec2/forms.py
index d3e55196a..bbacb0124 100644
--- a/horizon/dashboards/settings/ec2/forms.py
+++ b/horizon/dashboards/settings/ec2/forms.py
@@ -17,6 +17,7 @@
 import logging
 import tempfile
 import zipfile
+from contextlib import closing
 
 from django import http
 from django.template.loader import render_to_string
@@ -87,7 +88,7 @@ class DownloadX509Credentials(forms.SelfHandlingForm):
 
         try:
             temp_zip = tempfile.NamedTemporaryFile(delete=True)
-            with zipfile.ZipFile(temp_zip.name, mode='w') as archive:
+            with closing(zipfile.ZipFile(temp_zip.name, mode='w')) as archive:
                 archive.writestr('pk.pem', credentials.private_key)
                 archive.writestr('cert.pem', credentials.data)
                 archive.writestr('cacert.pem', cacert.data)