diff --git a/Doc/library/json.rst b/Doc/library/json.rst
index 758ebd45059..9bafcfe00f6 100644
--- a/Doc/library/json.rst
+++ b/Doc/library/json.rst
@@ -82,6 +82,7 @@ Extending :class:`JSONEncoder`::
     ...     def default(self, obj):
     ...         if isinstance(obj, complex):
     ...             return [obj.real, obj.imag]
+    ...         # Let the base class default method raise the TypeError
     ...         return json.JSONEncoder.default(self, obj)
     ...
     >>> json.dumps(2 + 1j, cls=ComplexEncoder)
@@ -426,6 +427,7 @@ Encoders and Decoders
                 pass
             else:
                 return list(iterable)
+            # Let the base class default method raise the TypeError
             return json.JSONEncoder.default(self, o)
 
 
diff --git a/Lib/json/encoder.py b/Lib/json/encoder.py
index 93b5ea7d5e0..39b550dbb0b 100644
--- a/Lib/json/encoder.py
+++ b/Lib/json/encoder.py
@@ -166,6 +166,7 @@ class JSONEncoder(object):
                     pass
                 else:
                     return list(iterable)
+                # Let the base class default method raise the TypeError
                 return JSONEncoder.default(self, o)
 
         """