Add an __all__ to html.entities.

Lib/html/entities.py

 """HTML character entity references."""
 
+__all__ = ['html5', 'name2codepoint', 'codepoint2name', 'entitydefs']
+
+
 # maps the HTML entity name to the Unicode codepoint
 name2codepoint = {
     'AElig':    0x00c6, # latin capital letter AE = latin capital ligature AE, U+00C6 ISOlat1

Misc/NEWS

@@ -121,6 +121,8 @@ Core and Builtins
 Library
 -------
 
+- Add an __all__ to html.entities.
+
 - Issue #15114: the strict mode and argument of HTMLParser, HTMLParser.error,
   and the HTMLParserError exception have been removed.