1 files changed, 3 insertions, 4 deletions
diff --git a/sphinx/util/jsonimpl.py b/sphinx/util/jsonimpl.py
index 557bc122f..ba47cf29f 100644
--- a/sphinx/util/jsonimpl.py
+++ b/sphinx/util/jsonimpl.py
@@ -10,20 +10,19 @@
 """
 
 import json
+from collections import UserString
 
 from six import text_type
-from six.moves import UserString
 
 if False:
     # For type annotation
     from typing import Any, IO  # NOQA
-    from sphinx.util.typing import unicode  # NOQA
 
 
 class SphinxJSONEncoder(json.JSONEncoder):
     """JSONEncoder subclass that forces translation proxies."""
     def default(self, obj):
-        # type: (Any) -> unicode
+        # type: (Any) -> str
         if isinstance(obj, UserString):
             return text_type(obj)
         return super(SphinxJSONEncoder, self).default(obj)
@@ -36,7 +35,7 @@ def dump(obj, fp, *args, **kwds):
 
 
 def dumps(obj, *args, **kwds):
-    # type: (Any, Any, Any) -> unicode
+    # type: (Any, Any, Any) -> str
     kwds['cls'] = SphinxJSONEncoder
     return json.dumps(obj, *args, **kwds)