Index: filters/urlencode.py
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new file mode 100644
--- /dev/null
+++ b/filters/urlencode.py
@@ -0,0 +1,21 @@
+# This file is part of the Adblock Plus website,
+# Copyright (C) 2006-2015 Eyeo GmbH
+#
+# Adblock Plus is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# Adblock Plus is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+
+import urllib
+
+# This can be removed once we can rely on having at least Jinja2 2.7.
+
+def urlencode(value):
+  return urllib.quote(value)
