diff --git a/src/calibre/srv/legacy.py b/src/calibre/srv/legacy.py
index 925115c946..4a68c0a316 100644
--- a/src/calibre/srv/legacy.py
+++ b/src/calibre/srv/legacy.py
@@ -19,7 +19,7 @@ from calibre.srv.routes import endpoint
 from calibre.srv.utils import get_library_data, http_date
 from calibre.utils.cleantext import clean_xml_chars
 from calibre.utils.date import dt_as_local, is_date_undefined, timestampfromdt
-from polyglot.builtins import iteritems, string_or_bytes, filter, as_bytes
+from polyglot.builtins import iteritems, string_or_bytes, filter, as_bytes, unicode_type
 from polyglot.urllib import urlencode
 
 # /mobile {{{