--- contrib/python/Werkzeug/py2/werkzeug/routing.py	(index)
+++ contrib/python/Werkzeug/py2/werkzeug/routing.py	(working tree)
@@ -2027,7 +2027,7 @@ class MapAdapter(object):
             (self.map.host_matching and host == self.server_name)
             or (not self.map.host_matching and domain_part == self.subdomain)
         ):
-            return "%s/%s" % (self.script_name.rstrip("/"), path.lstrip("/"))
+            return str("%s/%s" % (self.script_name.rstrip("/"), path.lstrip("/")))
         return str(
             "%s//%s%s/%s"
             % (