diff -r 26200f535296 Doc/library/json.rst
--- a/Doc/library/json.rst	Wed Oct 03 13:53:28 2012 +0530
+++ b/Doc/library/json.rst	Thu Oct 04 11:09:59 2012 +0530
@@ -82,6 +82,7 @@
     ...     def default(self, obj):
     ...         if isinstance(obj, complex):
     ...             return [obj.real, obj.imag]
+    ...         # Raises a TypeError by calling JSONEncoder.default
     ...         return json.JSONEncoder.default(self, obj)
     ...
     >>> json.dumps(2 + 1j, cls=ComplexEncoder)
@@ -409,6 +410,7 @@
                 pass
             else:
                 return list(iterable)
+            # Raises a TypeError by calling JSONEncoder.default
             return json.JSONEncoder.default(self, o)
 
 
diff -r 26200f535296 Lib/json/encoder.py
--- a/Lib/json/encoder.py	Wed Oct 03 13:53:28 2012 +0530
+++ b/Lib/json/encoder.py	Thu Oct 04 11:09:59 2012 +0530
@@ -163,6 +163,7 @@
                     pass
                 else:
                     return list(iterable)
+                # Raises a TypeError by calling JSONEncoder.default
                 return JSONEncoder.default(self, o)
 
         """