diff --git a/Lib/html/parser.py b/Lib/html/parser.py
--- a/Lib/html/parser.py
+++ b/Lib/html/parser.py
@@ -12,6 +12,8 @@
 import re
 import warnings
 
+__all__ = ['HTMLParser']
+
 # Regular expressions used for parsing
 
 interesting_normal = re.compile('[&<]')